MadModder

The Shop => Wood & Stuff => Topic started by: S. Heslop on December 17, 2014, 12:28:51 PM

Title: Drum/ Thickness Sander
Post by: S. Heslop on December 17, 2014, 12:28:51 PM
I've started working on a drum/ thickness sander to help with making skateboards, of all things, but it'll likely come in handy for some other stuff too.

This might be a bit of a slow project since I have no money (or job!).

(http://iforce.co.nz/i/csqcyfdo.xb3.jpg)
The plan so far. I haven't got a motor currently so I haven't dealt with that part in the plan yet.

(http://iforce.co.nz/i/b5zsp2kw.y2j.jpg)
My table saw isn't anywhere near wide enough for alot of the cuts, so i've had to do it the hard way.

(http://iforce.co.nz/i/uguww0bk.wnn.jpg)
Could still fit some stuff on for cross-cutting though. I'm cutting out the two boards that make the table surface.

(http://iforce.co.nz/i/rdenf0d4.vjq.jpg)
Then used the tablesaw and bandsaw to cut out the sides of the table, using printed templates.

(http://iforce.co.nz/i/w5kojzza.krb.jpg)
Grooves were routed into the sides. The table is going to have a conveyor belt on it, and the grooves are for adjusting the tension and tracking with some slides that fit in them.

(http://iforce.co.nz/i/df02z11i.4im.jpg)
The slides were also cut on the router table. I had trouble at first since I discovered that the surface of the router table is no longer anywhere near flat, so the boards raised up enough to make the channel a full millimeter wider at one end than the other. I countered this by building some push blocks so I could force the wood sit pressed against the table and re-cut the grooves.

(http://iforce.co.nz/i/4zwxiwce.myn.jpg)
Another problem I had was mucking up the order of operations, making it very difficult for me to drill the holes that the threaded rod (for adjustment) fits in. I routed a groove all the way across the bottom of the channels.

(http://iforce.co.nz/i/i3ddlhow.pzn.jpg)
And fitted in some lumps of wood to fill the gap.

(http://iforce.co.nz/i/wc1aw1q4.1te.jpg)
It also turned out that the birch plywood I was using for the sides and table wasn't flat either. I routed a groove in the surface slabs to accept a rod for pivoting (to adjust the depth of cut), which i'd positioned so that the concavity in the bow was towards the center of the two boards. Hopefully the bow in each board will cancel each other out.

(http://iforce.co.nz/i/44l4siuu.pl5.jpg)
When clamping it up I used two boards of actually flat plywood to hopefully encourage the table surface to remain flat once the glue dries.

With glue drying there's not alot more I can do today. Plus when it gets dark I don't have enough light in the garage to film stuff well.

Title: Re: Drum/ Thickness Sander
Post by: mattinker on December 17, 2014, 01:17:06 PM
What's wrong with of all things, making skate boards?

All the best, Matthew.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on December 17, 2014, 02:38:00 PM
What's wrong with of all things, making skate boards?

All the best, Matthew.

I got a friend who's interested in making them to sell and asked for my help. Myself I can't even stand up on a skateboard. I'm just not sure how to go about selling them though so i'm not too confident in the idea, but it should still be interesting to give it a go.

I've had a hard time sourcing maple veneer (at about 1.5mm thick) in the UK for a reasonable price, so the drum sander will be for making it myself. But with real high end skateboard decks costing £60, it's probably going to be tough keeping it profitable with the materials and labour involved. But we'll see.

My original goal was to make banjos to sell, and the drum sander will help with that too. Except to make banjos properly i'd need a big lathe, and I can't afford one and probably wont be able to for a while.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on December 17, 2014, 03:46:48 PM
This should be good!  :coffee:
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 13, 2015, 01:19:14 PM
It's been a while. Got around to doing a bit more.

(http://iforce.co.nz/i/dc5it34w.r3s.jpg)
Sides of the slab weren't quite flat or parallel so I trued them up on my crappy jointer/ planer. Doing this was guaranteed to nick the knives but it wouldn't fit onto my tablesaw or my router table unfortunately.

I'm also not sure if i'd recommend buying one of these combination tools, they have alot of problems and I haven't really bothered to try sort any of them out since buying it.

(http://iforce.co.nz/i/gfazwand.iho.jpg)
I worked out that the gap between the top of the table and those channels should be about 4.3mm, so I used some 4mm brass rods and pop can shims to space the parts. I also made sure it was lined up properly horizontally by checking the steel bar that passes through for squareness.

The sides were clamped to the slab and the screw holes were drilled after it was all lined up.

(http://iforce.co.nz/i/tymdblr1.f2k.jpg)
And that's the sides attached.


Title: Re: Drum/ Thickness Sander
Post by: Lew_Merrick_PE on January 14, 2015, 11:19:55 AM
S. Heslop -- I have made several variations on drum-type thickness sanders over the years on support of my original trade training as a luthier (lute and guitar maker).  The design that I find most useful is to use a piece of thick-wall tubing as the drum and then to spiral wrap (1-1/2 inch or 40 mm) wide strip abrasive media to the drum.  DOM (Drawn Over Mandrel) tubing typically only varies a couple of thousandth's of an inch (call it 0.05 mm) from perfectly cylindrical in lengths up to 20 inches (500 mm) (and your abrasive media will vary more than that), so the only real challenge is getting the tubing mounted on a shaft.  Personally, I make a press-fit plug that has a shoulder to fit the tube that I attache with (strong) set-screws.

I do not have access to my current beast (it is in storage due to a lack of space), but I built it back in the 1990's.  The thickness adjustment is a pivoted piece of laminated (good cabinet quality) plywood that is faced with UHMW polyethylene.  A high-tack conveyor belt drives the piece through the sander.  The run surface of the belt is 40 inches (basically 1 m) to support infeed and outfeed of guitar ribs.  I can hold a bit better than +/-.010 inches (+/-0.25 mm) using this set-up.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 15, 2015, 04:48:18 AM
S. Heslop -- I have made several variations on drum-type thickness sanders over the years on support of my original trade training as a luthier (lute and guitar maker).  The design that I find most useful is to use a piece of thick-wall tubing as the drum and then to spiral wrap (1-1/2 inch or 40 mm) wide strip abrasive media to the drum.  DOM (Drawn Over Mandrel) tubing typically only varies a couple of thousandth's of an inch (call it 0.05 mm) from perfectly cylindrical in lengths up to 20 inches (500 mm) (and your abrasive media will vary more than that), so the only real challenge is getting the tubing mounted on a shaft.  Personally, I make a press-fit plug that has a shoulder to fit the tube that I attache with (strong) set-screws.

I do not have access to my current beast (it is in storage due to a lack of space), but I built it back in the 1990's.  The thickness adjustment is a pivoted piece of laminated (good cabinet quality) plywood that is faced with UHMW polyethylene.  A high-tack conveyor belt drives the piece through the sander.  The run surface of the belt is 40 inches (basically 1 m) to support infeed and outfeed of guitar ribs.  I can hold a bit better than +/-.010 inches (+/-0.25 mm) using this set-up.

Shame you don't have access to the sander, i'd like to see it!

For the drum I was going to try making a stack of MDF disks and turning them round. Unfortunately I don't have a lathe big enough to try the pipe method, but i'll keep it in mind in case the MDF doesn't work out. I think the biggest risk with MDF is the stuff changing dimensions over time as it absorbs/ loses moisture.

How did you attach the sandpaper to the drum though? I was thinking about going with velcro since i've seen other people use that, but i'm still skeptical about if it'd hold or not (on the edges at least). The other method i've seen is to physically hold it at both ends with a sort of clamp/ screw and making the cutout in the drum for that might be easy with the MDF disks.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 15, 2015, 08:57:45 AM
Ran into a problem already. Got the MDF stacks for the rollers glued up, and started turning them true with this setup.

(http://iforce.co.nz/i/v04tnl4h.is2.jpg)

(http://iforce.co.nz/i/yuhnomxo.uyo.jpg)

The problem is that it's producing an undulated surface where the looser MDF in the middle... fluffs out.

(http://iforce.co.nz/i/perabkxg.jkh.jpg)

Still not sure on the solution. I'm thinking I could turn them down further and slip/ glue on a piece of PVC pipe and then turn that to size, or I could dilute down some varnish and try soak it into the MDF to harden it so it turns better. I've already messed with the cutting tool (chisel) geometry and angle a bit, and it didn't seem to make a difference. Nor did sanding it.

Oh one thing I don't think I mentioned is that i'm trying to build this without using the lathe at all, for the sake of the video. I'm also not going to use the pipe and end caps idea for these rollers since I want to try turning in a slight crown to see if it helps with tracking the conveyor belt.
Title: Re: Drum/ Thickness Sander
Post by: chipenter on January 15, 2015, 10:22:14 AM
Sand it with a solid flat block then seal it .
Title: Re: Drum/ Thickness Sander
Post by: awemawson on January 15, 2015, 11:15:32 AM
Make up a 50 / 50 pva glue / water solution and saturate it. Leave over night to dry then try turning it again, or possibly block sanding it
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 15, 2015, 11:57:36 AM
Make up a 50 / 50 pva glue / water solution and saturate it. Leave over night to dry then try turning it again, or possibly block sanding it

I did try sanding it and it didn't do much to help. I'll try the glue thing, although i'm a little worried the moisture will mess up the MDF. I guess if it doesnt work at all i'll just drive the shaft out and try making it again with plywood instead.
Title: Re: Drum/ Thickness Sander
Post by: Fergus OMore on January 15, 2015, 01:23:55 PM
The most obvious thing is 'Sanding Sealer' but if you are windy about PVA, any spirit based varnish left over from other DIY jobs should seal the MDF. Me, a few miles up the road from the Gill, I've used some old 2 part resin for a silly job that has passed its sell by date. Accelerated the gel a bit with a hairdryer.

OK. I'm 'with it' but there are proprietory Sealers for even wet and rotted wood. I did a rotten keelson on a dinghy from Derwent Reservoir with ordinary fibreglass resin and packed it glass in stages as the gel exothermed.

It' s dead easy. Mucky, yea

Cheers

Norman
Title: Re: Drum/ Thickness Sander
Post by: greenie on January 15, 2015, 05:45:10 PM

I did try sanding it and it didn't do much to help. I'll try the glue thing, although i'm a little worried the moisture will mess up the MDF. I guess if it doesnt work at all i'll just drive the shaft out and try making it again with plywood instead.


The sanding drum is without doubt, the most important bit of the whole build.

If you can not get the drum to be stable, then you are going to have variations in the thickness of whatever you put through it. Chipboard as you have already found, is nowhere near stable, plywood will be of a similar thing with the way the grain is layered when making the ply.

My opinion is to make it from steel if possible, that way it is very stable and the only variances will be caused by the temperature. Possibly it might be worthwhile, inquiring about having it made from some metal instead of some form of assorted timber products.

Another alternative to chipboard or plywood, is to make it from a solid bit of every dense hard wood, that way it will be reasonably stable.

Your choice on what you use for the drum, but keep in mind what has been stated.
Title: Re: Drum/ Thickness Sander
Post by: greenie on January 15, 2015, 05:58:46 PM
I've started working on a drum/ thickness sander to help with making skateboards, of all things, but it'll likely come in handy for some other stuff too.

This might be a bit of a slow project since I have no money (or job!).

(http://iforce.co.nz/i/csqcyfdo.xb3.jpg)



A bit overly ambitious with a motorised in-feed roller when the readies are a bit on the short side, why not scrap that idea and use a bit of glass that's stuck onto the adjustable table, to allow the product to be pushed through with the least resistance. Much, much cheaper if you use a push stick to shove the product through it, eh.

Good to see you have allowed for a cover over the sanding drum, make sure you attach a vacuum cleaner to it, to suck ALL that dust away.
Title: Re: Drum/ Thickness Sander
Post by: Fergus OMore on January 15, 2015, 06:07:21 PM
The sanding drum is without doubt, the most important bit of the whole build.

If you can not get the drum to be stable, then you are going to have variations in the thickness of whatever you put through it. Chipboard as you have already found, is nowhere near stable, plywood will be of a similar thing with the way the grain is layered when making the ply.

My opinion is to make it from steel if possible, that way it is very stable and the only variances will be caused by the temperature. Possibly it might be worthwhile, inquiring about having it made from some metal instead of some form of assorted timber products.

Another alternative to chipboard or plywood, is to make it from a solid bit of every dense hard wood, that way it will be reasonably stable.

Your choice on what you use for the drum, but keep in mind what has been stated.

All very interesting but********************

Just over the hill from where Mr Heslop lives is a huge American owned firm  which made rollers from rubber- which was actually blown onto a mandrel and used in the spinning industry- after being ground -precisely.
The foreman was and maybe still is a member of TSMEE.

My belt sander was from Picador and was aluminium or Chinese metal( I forget) and my present ones are actually plastic.

But here's the rub( pun intended), a belt sander is NOT and never has been accurate. There is a lot of information which was written about it elsewhere- probably Model Engineer- but it ain't going to produce FLAT surfaces.

Sorry and all that

Norman
Title: Re: Drum/ Thickness Sander
Post by: greenie on January 15, 2015, 06:31:44 PM

All very interesting but********************

Just over the hill from where Mr Heslop lives is a huge American owned firm  which made rollers from rubber- which was actually blown onto a mandrel and used in the spinning industry- after being ground -precisely.
The foreman was and maybe still is a member of TSMEE.

My belt sander was from Picador and was aluminium or Chinese metal( I forget) and my present ones are actually plastic.

But here's the rub( pun intended), a belt sander is NOT and never has been accurate. There is a lot of information which was written about it elsewhere- probably Model Engineer- but it ain't going to produce FLAT surfaces.

Sorry and all that

Norman


I'll agree with you that a BELT sander is not very accurate AT ALL.

BUT your forgetting what is being made here, it aint NO belt sander, it's a drum sander, it's got a rotating drum which does the sanding.
If the rotating drum has been made round and straight, the sanding medium applied so that it is very constant in it's thickness, then the machine can and will reproduce the very same results constantly. Far superior to what a belt sander will ever be able to reproduce.

You can get a drum sander that is very accurate, to with-in the variances of + or - 0.001", I have made one that will do that quite adequately each and every time I use it. These measurements can be proven with a micrometer time after time, so don't try and tell me that it can't be done, -- it can.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on January 15, 2015, 07:06:35 PM
Simon. just lurking here in the peanut gallery, hoping you're doing what you want.  :thumbup:  :beer:
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 16, 2015, 01:16:05 AM
A bit overly ambitious with a motorised in-feed roller

Absolutely, but it's the part of the project I care the most about. I've made it so long so I can use a sanding belt as the conveyor surface. There's alot of information on drum sanders where you just push the wood through, but the few people that have built conveyor belts are tragically vague about how they work. Plus i've read a few people saying they were difficult to get working and they eventually gave up trying, and that sounds like a challenge.

As for the stability of MDF, it's really the ideal for stuff like this since it doesn't have a directional grain. If the drum is properly sealed it should hold up fairly well, and if it does warp a bit you can true it up by just sending a bit of sandpaper on a board through (or with a sandpaper conveyor you could just raise the table till it touches). If I used solid wood it'd expand along the grain to make the drum oval shaped, and truing it up would be futile with it going back and forth with the seasons.

Simon. just lurking here in the peanut gallery, hoping you're doing what you want.  :thumbup:  :beer:

Haha, thanks.

Yeah i'm trying to build a thing that should be repeatable by anyone else. Mostly I hate seeing videos where a guy uses, say, parts from an old tablesaw to build something else, and I imagine it's equally irritating for people when they see me using a metal lathe in a video about woodworking. Plus it's fun finding ways around problems.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on January 16, 2015, 07:41:56 AM
Plus it's fun finding ways around problems.
:thumbup: :beer:
Title: Re: Drum/ Thickness Sander
Post by: Spurry on January 16, 2015, 08:40:34 AM

As for the stability of MDF, it's really the ideal for stuff like this since it doesn't have a directional grain.


Have you considered using the green MDF. It's so much more stable than the normal brown stuff. I would hesitate to say it's waterproof, but water resist is how they advertise it.
Pete

Title: Re: Drum/ Thickness Sander
Post by: vtsteam on January 16, 2015, 09:10:16 AM
Simon, random thoughts per your own design intention to true a wooden roller:

Traditional, non water-based polyurethane varnish won't dissolve the MDF binder and is thin enough to penetrate deeply and harden fibers uniformly. Polyurethanes are probably the most vapor resistant of any coating. Including epoxies, and more widely available.

Sanding to remove contours using a block against a turned wood piece is difficult to achieve. A rotary sander arranged like a shaft grinder to keep a fixed distance from the axis of the turned part will remove only the high spots if the pressure is light enough. See John Hill's redneck shaft finisher thread for the general principle.

Finally, if you do decide to give up on the MDF, a traditional way of using conventional wood in a turned design that must remain dimensionally stable is to rip strips into 45 degree beveled staves and glue together into an octagon section, then turn to round. The grain orientation should be consistent in the staves. For large turned sections, the joints should be splined.

Hope that helps as FYI suggestions only!  :bow:







Title: Re: Drum/ Thickness Sander
Post by: greenie on January 16, 2015, 05:56:24 PM

Absolutely, but it's the part of the project I care the most about. I've made it so long so I can use a sanding belt as the conveyor surface. There's alot of information on drum sanders where you just push the wood through, but the few people that have built conveyor belts are tragically vague about how they work. Plus i've read a few people saying they were difficult to get working and they eventually gave up trying, and that sounds like a challenge.

 Plus it's fun finding ways around problems.


Simon, hereís something else to ponder over.

With the infeed roller using a sanding belt to feed the timber through the drum sander, will this not create one sanding surface working against another sanding surface ? One action of trying to pull/push/drag the timber one direction whilst the rotating drum is trying to do the exact opposite action. Therefore creating a double sanding action and negating the effect of the infeed belt altogether, as it does require a bit of pushing pressure on the timber, to actually hand push the timber through the machine, against the rotating action of the sanding drum.

So one light weight piece of timber sitting on top of an infeed belt, without any downward pressure to hold it against that infeed belt, then the forward movement of the timber will stop and allow the drum sander to just either spit it straight back out, or, allow the front edge of the stationary bit of timber to be chewed away by the drum sander, whilst the infeed belt is chewing away at the the underside of the timber, until there is NO more grip/resistance from the belt underneath, and then just spit the timber straight back out anyway.

What does a normal blade thicknesses actually use, to push/drag the timber through the machine to "negate" the effect of the blades pushing/spitting the timber back out of the machine ?
Possibly some type of similar set-up, might be required for this design of yours as well.

Either more infeed rollers will be required to add downward pressure onto the timber work-piece, whilst it is on the infeed belt, to counteract the forces of the rotating sanding drum, or, forget that idea as others have done, because of the above problems.

The alternative to an infeed belt is to glue a piece of glass over the rise and fall table, this will virtually eliminate any resistance/drag on the timber work-piece, from the surface of the rise and fall table. By you using a push stick to control/maintain the infeed pressure, you can now have a definite feel for what is happening, when the timber is being mutilated by the sanding drum. 

Itís your choice on what you do, just a few more ideas for you to mull over.

regards  greenie   :loco:


Title: Re: Drum/ Thickness Sander
Post by: mattinker on January 17, 2015, 01:34:34 AM
I'm really not in agreement with Greenie, your sanding belt drive sounds interesting, I can't see any way that if you set it up right it will double sand, the belt is there to grip and not slide over the wood. I avoid MDF at all costs, it's full of formalin based glue which is pretty poisonous! If you must use MDF, Andrews sugestion of PVA wood glue diluted with water is a very good way to go, dousing it once in water has not affect at all on the MDF.

I'm following this with great interest!

Regards, Matthew.
Title: Re: Drum/ Thickness Sander
Post by: Fergus OMore on January 17, 2015, 03:09:29 AM
This MDF thing is interesting.  The largest man made forest is just north of me.
As a natural byproduct- it had been designed to supply pit props in WW2, there is an Austrian firm called Egger.
It set up a huge MDF factory to absorb the supply- the coal mines had closed- it is only 20 miles from me- and Simon.

No one can miss it at Hexham. It bursts into flames a bit lile a volcano.  One would have thought that - well, one would have thought.

Ahh well

Norman
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 17, 2015, 05:26:59 AM
Yeah i'm not convinced about the double sand thing either. The conveyor belt is going to move fairly slow, there'll be more surface area with the part flat against the sandpaper belt, and you're only going to be making fairly light cuts with a thickness sander to begin with. But we'll see.

One thing I have thought about is, since I want to use this to primarily smooth and thickness 1.5mm veneers cut on a bandsaw (a bandsaw i've yet to make), which will probably end up being fairly warped at that thickness, I might still need some sort of infeed/ outfeed roller to hold them flat against the table as they pass through.

Also I do really like Kielder forest. I never knew that it supplied the Hexham chipboard factory, but I suppose that makes sense. I'd mostly assumed it was used as fuel.
Title: Re: Drum/ Thickness Sander
Post by: Fergus OMore on January 17, 2015, 06:57:23 AM
When all is said and done, the abrasive belts are required. They have to be costed, obtained and glued.

Not cheap.  :bang:

Regards

Norman
Title: Re: Drum/ Thickness Sander
Post by: Manxmodder on January 17, 2015, 11:19:11 AM
Hi Simon, this is an interesting project you've started and I'll be watching how it develops as you progress.

I just did a bit of googling for info and found this link to various drum sanders. The Jet sander seems to use a conveyer belt system similar to your design and if you look at the specs you can gather some useful info about drum size and feeds etc......Link: http://www.rockler.com/jet-benchtop-sander-1hp

.....OZ.
Title: Re: Drum/ Thickness Sander
Post by: Fergus OMore on January 17, 2015, 11:56:08 AM
And the provision to 'crown' the rollers to keep the belt 'on track'?

Let's say that I am farting about with my bandsaw- and trying to replace a broken twin clarinet stand for my wife's A and Bflat clarinets.

Said I'd been there :poke:


Norman
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 21, 2015, 12:57:30 PM
(http://iforce.co.nz/i/5kshm2zn.4cx.jpg)

I've been a little apprehensive about the idea but gave it a go today. I'd done some tests on spare disks of MDF and didn't have any luck getting the diluted glue to penetrate to any depth, even trying to add a bit of vacuum with a vacuum cleaner. It might be a case of just getting it fairly close to final dimension and soaking it for a while to get just the surface hard. I'm still also unsure how the MDF will react to being soaked in water, as it'll probably take months to dry out fully (especially if the glue seals it), so the whole thing might warp after a while.

But with no other options i'm aware of, im still trying it. If it doesn't work out i'll just replace the MDF with plywood like I mentioned earlier.
Title: Re: Drum/ Thickness Sander
Post by: NormanV on January 21, 2015, 01:30:05 PM
The trouble with PVA is that it dries rubbery and will clog up the abrasive paper that you use to smooth the roller. Varnish would do a better job of hardening the MDF roller in preparation for sanding.
Title: Re: Drum/ Thickness Sander
Post by: Fergus OMore on January 21, 2015, 01:37:57 PM
Simon

If there is no metal insert and you have pva still wet, why not microwave it? After all, it is a way to season timber.

Regards

Norman
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 21, 2015, 02:12:55 PM
The trouble with PVA is that it dries rubbery and will clog up the abrasive paper that you use to smooth the roller. Varnish would do a better job of hardening the MDF roller in preparation for sanding.

I did consider varnish, but I preferred the idea of splashing about PVA glue to anything solvent based.

I've been thinking about tool geometries a bit. In past experience, turning wood freehand with anything that has a fairly positive rake is a recipe for disaster, but it might have more success in cutting the MDF if I can keep it under control. The way it's set up at the moment, there should be alot of support to prevent the tool from digging in. The other option might be using some sort of router sled to route the thing round as it spins.

I think i've got too much time to think while waiting for this stuff. I'm also too scared about knocking the thing over and spilling it everywhere if I try get on with something else in the meantime.

If there is no metal insert and you have pva still wet, why not microwave it? After all, it is a way to season timber.

Unfortunately there is a metal insert, but that's an idea i'll probably keep in mind for the future.
Title: Re: Drum/ Thickness Sander
Post by: RussellT on January 21, 2015, 05:17:32 PM
It sounds a lot of trouble.

I'd try sleeving it with PVC pipe or looking for a roller out of an old printer or typewriter.

You could also try polyester resin (fibreglass stuff) or car body filler to stabilise the surface.  It doesn't take long to set although a bit of extra hardener does no harm in the current weather.

Russell
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 21, 2015, 06:20:44 PM
You could also try polyester resin (fibreglass stuff) or car body filler to stabilise the surface.  It doesn't take long to set although a bit of extra hardener does no harm in the current weather.

That's a good idea.

I did think about sleeving it with PVC pipe but I couldn't find any in the dimensions required, which was a shame.
Title: Re: Drum/ Thickness Sander
Post by: SwarfnStuff on January 22, 2015, 12:35:23 AM
"I did consider varnish, but I preferred the idea of splashing about PVA glue to anything solvent based."  Probably too late, but there is water based floor varnish that just may do the job. The solvent base I guess is good old fashioned water and it dries hard enough for floor treatment.
Good job so farm
John B
Title: Re: Drum/ Thickness Sander
Post by: Fergus OMore on January 22, 2015, 03:46:36 AM
.

I did think about sleeving it with PVC pipe but I couldn't find any in the dimensions required, which was a shame.

Oversize plastic gutter pipe can be cut and heat sealed with a soldering iron.

I'm thinking about a use for scrap plastic. Got a broken garden table to re-cycle :bang:

Norman
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 23, 2015, 05:50:11 AM
(http://iforce.co.nz/i/tifentkb.3ps.jpg)

All this waiting is killing me. I dried one of them out on a radiator and it cracked a bit, which I was actually happy to see since it was evidence it was actually drying and that a good amount of the stuff managed to soak in. It'd probably be prudent to let it stabilize for a while in the garage though, but i'm not sure how much longer I can stomach waiting.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 23, 2015, 07:37:55 AM
Well that's too bad, it didn't work. Nor did different tool geometries.

I guess my options are to find a piece of PVC pipe and see how easily that turns (I doubt it'd turn too easily), use a piece of PVC pipe and mould some sort of body filler/ epoxy thing (I also can't imagine body filler turning too pleasantly without chunks of it chipping out), or I could scrap the MDF and try again with plywood.

I think I might just go for plywood. I'm not so hot on the idea of using this MDF any more since, after being wetted and dried on a radiator, it probably won't stay the same shape unless I leave it for a month to stabilize. Plus I have the plywood on hand.

That said, there's probably a likelihood that i'll experience some chipping with the plywood too, what with turning it on the end grain. Although Matthias Wandel had success turning plywood for bandsaw wheels.
Title: Re: Drum/ Thickness Sander
Post by: Manxmodder on January 23, 2015, 03:06:12 PM
The success of plywood will very much depend on the type and quality.

Birch ply would probably be a good bet,but it is not cheap. I would give serious consideration to the making a glued up roller blank from staves with grain longitudinaly as VT Steam has previously mentioned.....OZ.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on January 23, 2015, 04:19:04 PM
Just rip strips with the blade set to 45 degrees. Use real wood. BYU.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 26, 2015, 11:15:59 AM
Let there be squares.
(http://iforce.co.nz/i/w5ztnjj4.sp4.jpg)
(http://iforce.co.nz/i/oziejfq0.bn4.jpg)
(http://iforce.co.nz/i/wzqsaxwn.5on.jpg)

(http://iforce.co.nz/i/pgbngybh.lhf.jpg)
Had a bit of an accident trying to grind a tool to not tear out the wood as much.

(http://iforce.co.nz/i/4sieuric.tws.jpg)
(http://iforce.co.nz/i/txjrdg2f.h0n.jpg)
Eventually got it round with only a few chipouts. These could be filled but i'm not sure if it'd affect things too much.

Now i've got to make the second roller, which i'll probably cut the corners off the squares before gluing it up so there's less to remove in turning.
Title: Re: Drum/ Thickness Sander
Post by: micktoon on January 26, 2015, 04:07:39 PM
Hi Simon , looks like the plywood must have been quite decent stuff , the worse quality stuff seems to have so many voids in it these days I doubt of you could have turned it like that. It looks like it has turned out not bad at all so hopefully will do the job for you.
 I had been going to say for the car body filler idea , I think better then turning it would have been to have a sander passing back and forward as the cylinder you were working on rotated, this might still be an idea to finish off and crown the plywood version, I am thinking a hand held electric half sheet type flat base sander ?

 Good work .
  Cheers Mick.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 26, 2015, 05:04:04 PM
I did sand it a bit, and tried sand it more at the edges than the middle to maybe give it a bit of a crown. But it didn't produce anything measurable and I thought i'd try leaving the crown for now and seeing how it tracks on its own. The portable belt sander I have doesn't seem to have any crown at all, but does have a flange that keeps the belt from slipping off.

Yeah i'm really surprised by the quality of the plywood too. There's a few ugly bits where the edges of plies meet and overlap. Of all the squares I cut I only had to reject 3 for voids/ layers coming loose. It wasn't expensive plywood too, just WBP from Doves in Newburn.

Also I just glued up the next roller. When trying to shake glue out the bottle I managed to get it all over my Fanciest Shirt. Hopefully it washes of or i'll have no shirts left without holes or glue on them.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 28, 2015, 06:41:46 PM
Finished the second roller. Now i'm just waiting on the belt and some bearings to get delivered.

Something i've left late to really consider is the motor i'm gonna use. There's a second hand shop nearby with a whole shelf full of motors that look perfect for the job, but the guy is unfortunately refusing to sell them individually since they come as a set for a jacuzzi. If I had the money i'd probably buy the lot.

A while back a guy going by malbenbut gave me a motor for free. I'd been saving it for a bandsaw i'm hoping to build after this sander is complete, but if I can't find a more suitable motor before then I'll just use it with this.

(http://iforce.co.nz/i/ze0fjgtv.5s0.jpg)

Another reason i've been avoiding using it is because it's so big I figured it wouldn't fit, but I decided to measure it up anyways and it just barely fits...

(http://iforce.co.nz/i/i3hmfm30.cl5.jpg)

Of course I could always move stuff around to accommodate it better since I haven't started building the body yet. But i'd rather at least avoid making the thing any taller.
Title: Re: Drum/ Thickness Sander
Post by: greenie on January 28, 2015, 09:47:16 PM
Have you worked out what the "surface speed" for the sanding roller will be, too slow and it will take forever to remove anything, then if it's too fast it will burn the finish on the timber ?
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 29, 2015, 09:30:07 AM
Haven't worked out any surface speed, but i've found commercial sanders quoted at running 1400rpm with the same sized drum as i'm going for.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 30, 2015, 10:19:49 AM
(http://iforce.co.nz/i/wih3m0cf.o5x.jpg)

The stuff arrived today, surprisingly early. I got the belt cut, terribly though. I feel a bit silly because it's only about 10mm wider than the table, and I should've built the table to match the belt.  But I was planning on using some 'real' conveyor belt material at first, but couldn't find any for sale or any information on how to splice it (other than product pitches).

Anyways, as predicted, there's problems with it tracking. I spent a while tweaking it without any luck. With so much to adjust I'm not really too concerned about it tracking in both forwards and reverse though.

I suppose i'll try crowning the drive roller more heavily to begin with.

In all honesty I was sort of hoping to have a lazy day today, but the stuff arriving has made me feel like I need to do at least some work on it.
Title: Re: Drum/ Thickness Sander
Post by: DMIOM on January 30, 2015, 10:40:56 AM
It might be worth considering lining the two vertical sides where the edge of the belt will touch/drag with Formica or similar?
Title: Re: Drum/ Thickness Sander
Post by: Fergus OMore on January 30, 2015, 11:01:08 AM
Simon
             Probably your supplier at a reasonably  approachable price is Wickes. I bought a long roll- about 12 metres long but only 10cm wide. It's about £12 a roll. How to join it is any bodies guess. All that I can tell you is that I bought stuff for an old Picador but it was only about 3" wide. The firm was Davis Abrasives then in Byker and is now in Cramlington. The joints were diagonally cut and scarfed and glued.

Maybe this helps. Let me know

Norman
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 30, 2015, 11:56:32 AM
It might be worth considering lining the two vertical sides where the edge of the belt will touch/drag with Formica or similar?

Yeah I was considering something like that if I couldn't get the belt to track at all. The cutouts to let the drum reach the table though would be a problem since the belt looks like its trying to ride up over there, since the seam on the straight side isn't perfectly lined up.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 30, 2015, 11:57:03 AM
Simon
             Probably your supplier at a reasonably  approachable price is Wickes. I bought a long roll- about 12 metres long but only 10cm wide. It's about £12 a roll. How to join it is any bodies guess. All that I can tell you is that I bought stuff for an old Picador but it was only about 3" wide. The firm was Davis Abrasives then in Byker and is now in Cramlington. The joints were diagonally cut and scarfed and glued.

Maybe this helps. Let me know

Norman

Hopefully this sanding belt is going to work fine, but i'll keep that in mind if it doesn't.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 30, 2015, 02:12:19 PM
Sanded more of a crown into the rollers (measures about 1mm wider diameter in the middle) and it seems to be tracking now. Although there's a strange squeaking/ knocking sound coming from the roller itself that I can't identify. My best guess is that it's the belt sort of slipping in parts due to the wider diameter in the middle.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 31, 2015, 04:10:30 PM
Went and bought some electric stuff today to build a PWM speed controller for a car windscreen wiper motor. I could've just bought a controller from ebay but i've been wanting to learn some electronics for a while, and this gives me an excuse.

(http://iforce.co.nz/i/a5b3i1ig.uvm.jpg)
It took a few tries to get something working. Keep in mind I really don't know alot about electronics besides the basics. I was first going with some more complicated diagrams i'd found online, specifically for PWM speed controllers, and I must've been mucking up the wiring somehow. So eventually I looked up some 555 timer stuff and found a very simple (http://www.555-timer-circuits.com/images/astable-mode-schematic.gif) diagram that I was able to successfully build.

(http://iforce.co.nz/i/jkjqii2k.55q.jpg)
(http://iforce.co.nz/i/twfo3rb0.4sy.jpg)
It's not without problems though. At about 75% duty cycle the wavelength of the signal starts to increase. I probably need to read up on 555 timers and play around with them more.

Glad I bought the oscilloscope though! I would've really been lost without it.
Title: Re: Drum/ Thickness Sander
Post by: Bluechip on January 31, 2015, 06:06:18 PM
I presume your pot. is linear, not log or semi-log ???

Which is my usual antic ....  :loco:

Dave
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on January 31, 2015, 06:22:55 PM
Yeah, it's linear. I got some 47k and 100k ones. I was considering getting some log ones too but ended up being in a hurry making the shopping list and forgot to ask in the shop.

What difference would logarithmic pots make? Just give me an easier time fine adjusting the small range where the pot actually changes the motor speed?
Title: Re: Drum/ Thickness Sander
Post by: Bluechip on January 31, 2015, 06:34:17 PM
Nope ...  Should be Linear. The frequency would drop very rapidly as the resistance increases.

eg ... say you had a 100k log pot the resistance change for the first ( say) 10 deg. would be a whole lot less than the last 10 deg.

Have not used 555's for PWM for ages, gone onto PIC uControllers .. Smartarse    :D

IIRC this is the cct. I used to use .. is it the same as yours ...

Dave

EDIT Rb is a linear Pot ....

Or it might have been this ...   :scratch:

Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 01, 2015, 06:22:04 AM
Whew, was worried i'd bought the wrong kinds of pots.

Microcontrollers are my eventual goal with electronics, but I figured it'd be best to figure out how discrete components work first. In the past i've tried reading books on the subject, but i've never found much stuff that isn't either incredibly theory heavy with little practical stuff, or stuff that just shows circuit diagrams with no explanation as to what anything does.

Thanks for the diagrams though. I'll try them out and see how they go.
Title: Re: Drum/ Thickness Sander
Post by: Bluechip on February 01, 2015, 07:07:27 AM
Most of the stuff you need to know about '555's in here  :thumbup:

http://www.amazon.co.uk/Integrated-Circuit-555-Projects-BP/dp/0859340473

PS The two BATxx Schottky diodes can be 1N4148's, makes no significant difference.

IIRC the 2nd circuit does not affect the base PWM frequency ...

Dave
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 01, 2015, 10:30:41 AM
That second diagram works much better at controlling the speed. Also produces a nicer square wave without the high points (inrush?). It does change the base frequency though, but i'm not sure if that is really a problem.
Title: Re: Drum/ Thickness Sander
Post by: Bluechip on February 01, 2015, 11:36:01 AM
It may well alter the frequency a bit ... it's a good few years since I did PWM with a 555.

Once you get into PWM on PICs its much more stable and very easy to change by code rather than oiking out the soldering iron.

If you're using breadboards I wouldn't bother about the glitching .. it does happen as you have a poor layout and contacts. Been there many times looking for non-existent problems ...  :palm:

If you want to 'scope it I would swap the motor for a resistor, no noise/ spikes from the commutator, and the sync. is better.

Post your original circuit ???

Dave
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 01, 2015, 01:21:02 PM
I'm not even sure where the original circuit was. I just found it via a Google image search.

I was looking up more 555 stuff and took another look at that website I got the real simple diagram from and found a more specific one.

http://www.555-timer-circuits.com/motor-pwm.html

And built it! There's an error in the diagram with one of the diodes backwards, that I wouldn't have noticed except that the two diode thing looked similar to the one in your second diagram.
(http://iforce.co.nz/i/bw1wgojs.kly.jpg)

The results are pretty good. The wavelength stays the same for most of the range, plus the pulse width ranges from very narrow to almost fully on.
(http://iforce.co.nz/i/cienckef.yre.jpg)
(http://iforce.co.nz/i/qliszqhx.bwu.jpg)
(http://iforce.co.nz/i/nqdan2dg.g41.jpg)

The slight sawtooth shape disappeared with a resistor connected in place of the motor like suggested.

I think I might stick with this one since it seems to be working fine. I'll have to leave soldering it up properly till tomorrow since I'll need the daylight for recording it.
Title: Re: Drum/ Thickness Sander
Post by: Bluechip on February 01, 2015, 03:12:39 PM
Have a look at the power rail while it's working.

The spikes may well be coming from there, you should really put a decoupling capacitor ( 22uF - ish ? ) right next to the chip Vcc pin to deck. The non-cmos 555's crowbar supplies like the devil.

IIRC the 7555 is the cmos version which does not do it so much ...  :thumbup:

It'll work  :ddb:  in my working life I've scoped industrial stuff and it's grim  :zap: but it ekkles ...  :lol:

Dave
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 02, 2015, 11:06:29 AM
Got the circuit made, with the decoupling cap and all which really helped reduce the spikes. Hopefully it'll work just fine with the bigger motor, that i've yet to buy.

It's ugly but i'm still really pleased with it. I should probably try get the flux off. I wonder if methylated spirits will work.

(http://iforce.co.nz/i/ldevscmz.k0k.jpg)
(http://iforce.co.nz/i/jxrd5ptb.eru.jpg)

Thanks Dave for the help while building it!
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on February 02, 2015, 11:24:27 AM
I've been following along with great interest, Simon, just not a lot to say, except keep up the good work!  :coffee: :thumbup: :beer:
Title: Re: Drum/ Thickness Sander
Post by: awemawson on February 02, 2015, 12:15:48 PM
I use spray carburetor cleaner and an old toothbrush to remove flux residues after soldering. If you are neat changing a component it's hard to tell you've been there  :clap:
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 04, 2015, 12:30:03 PM
I've been following along with great interest, Simon, just not a lot to say, except keep up the good work!  :coffee: :thumbup: :beer:

Thanks! I'm more than familiar with that feeling too.

Did some stuff on the body today. Sides were cut out with paper templates and an assortment of tools.
(http://iforce.co.nz/i/5qhtnt3j.3pl.jpg)

And the base was cut with rabbets to match the width of the tilting table part. Wasn't sure if I should've made it a little oversize or not, but I just ended up making it match. I figure if the sides have to pull in a millimeter when clamping the table in place, it might pull the drum out of alignment a bit.
(http://iforce.co.nz/i/cxglfsfi.iqr.jpg)

It's all just dry assembled here. I'll leave glueing it up for tomorrow. I've also managed to misplace the third 12mm bar for the table pivot, which I can't find anywhere. It's probably rolled under a bench or something.
(http://iforce.co.nz/i/4c5kg343.e0q.jpg)
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 04, 2015, 02:55:34 PM
I found the third bar. It was on the floor and buried in sawdust.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on February 04, 2015, 08:11:27 PM
I found the third bar. It was on the floor and buried in sawdust.

And I'm more than familiar with THAT feeling!!!  :lol:
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 05, 2015, 11:23:17 AM
(http://iforce.co.nz/i/js1xw41l.wsl.jpg)

Went into the garage to measure a thing and ended up making this. It's a hole cutter, for cutting holes about the right size for the 47mm bearings. Still need to grind the toolbit, as well as buy a drill bit that's a good fit with the hole.

Thought I was being clever drilling the hole for the drill bit with the same drill, but it made a way oversized hole. I guess I didn't grind the bit very well!
Title: Re: Drum/ Thickness Sander
Post by: malbenbut on February 06, 2015, 04:40:25 AM
I can buy a speed control up to 50v dc input from EBAY cheaper than I can buy the components in UK to make one.

MBB
Title: Re: Drum/ Thickness Sander
Post by: Fergus OMore on February 06, 2015, 12:19:29 PM
Doing 'the shopping' at Aldi and Lidl. Next week, Lidl has a pillar drill for £49.99. I've got one when Aldi's had them( probably the same). Looked at mine and thought that I could put it on my lathe saddle. Mebbe bit of fiddling with the cast iron base but dead useful. Thought that you might be interested

Norman
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 08, 2015, 01:58:16 PM
Squares II: Return of the squares

(http://iforce.co.nz/i/jcygbe3f.qcs.jpg)
(http://iforce.co.nz/i/ulw5ifav.sx2.jpg)
I spotted the middle with a spade bit.

(http://iforce.co.nz/i/igqapm4y.xss.jpg)
(http://iforce.co.nz/i/oh5pv03p.qhr.jpg)
I'm cutting off the excess so there's less to turn. It's also probably safer to be doing less of an interrupted cut.

(http://iforce.co.nz/i/xxdtsr5r.hkp.jpg)
And drilled all the way through. I need 23 of these and i've made that and one spare. I'd actually spent most of Saturday thinking about how i'd drill a 20mm hole without a 20mm bit, until I remembered I had the spade bits hidden somewhere.


(http://iforce.co.nz/i/h3xxo0gy.5w1.jpg)
I've also figured out how i'm going to hold the paper on. At first I was planning to use hook and loop sandpaper, but it's extraordinarily expensive. So I'm going to leave the two edge disks unglued, but held on with screws, so that after they're turned round I can remove them and cut segments out, and use the cutout to retain the edges of the paper.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on February 08, 2015, 02:38:55 PM
Simon when roughing out squares to circles on the bandsaw, drill a tight hole in a piece of scrap for a nail, and press it through. Turn it over so it stands vertical, point up. Clamp the scrap to the bandsaw table with the nail sticking up. set the distance of the nail to the blade to equal the rough radius you want. Then put a hole through the center of your blanks for a slip fit on the nail.

To use, put a blank on the stationary nail axle, and rotate the blank into the blade to cut the circle. This works best if you have a groove for a miter gauge in your bandsaw table, and put a tongue on the bottom of the scrap base so you can slide it in toward the blade, rather than just clamp it. You can then cut circles of any diameter, just by sliding in or out.

You can also cut cone segments this way by tilting the table to give an angle cut.

And you can cut rings this way, too.

Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 08, 2015, 03:56:58 PM
Simon when roughing out squares to circles on the bandsaw, drill a tight hole in a piece of scrap for a nail, and press it through. Turn it over so it stands vertical, point up. Clamp the scrap to the bandsaw table with the nail sticking up. set the distance of the nail to the blade to equal the rough radius you want. Then put a hole through the center of your blanks for a slip fit on the nail.

To use, put a blank on the stationary nail axle, and rotate the blank into the blade to cut the circle. This works best if you have a groove for a miter gauge in your bandsaw table, and put a tongue on the bottom of the scrap base so you can slide it in toward the blade, rather than just clamp it. You can then cut circles of any diameter, just by sliding in or out.

You can also cut cone segments this way by tilting the table to give an angle cut.

And you can cut rings this way, too.

Thanks for the tip but I don't think that'd work so well with my bandsaw. The blade likes to drift about so I need to cut freehand to try steer it. It's a pretty lousy bandsaw in general, the whole thing shakes as it runs since the three wheels are pretty far eccentric. Still beats using an upside down jigsaw!

A better bandsaw has been on my list of things to build for a while now. I think I still need to tidy up the garage a bunch after finishing this sander though. Still got the dust collector to finish, and I need to find a place to keep that bike (i'm thinking about strapping it to the ceiling).
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 09, 2015, 08:53:28 PM
Nearly gave myself a hernia today trying to push the disks on.
(http://iforce.co.nz/i/er3ievxg.0kb.jpg)

Ended up making a rubbish reamer to get the holes a bit bigger. Now the whole stack is glued up and drying.
(http://iforce.co.nz/i/om3ebs04.j1e.jpg)

Been having trouble sleeping the last few days, spent an hour in bed thinking about how to re-arrange the garage to fit more stuff in. If I move that tool chest Rob Wilson gave me behind the drill press, I could fit the planer and sander onto the short bench at the back of the garage. It'd also put the chest in a more convenient location. I can barely get at it where it is now.
(http://iforce.co.nz/i/w3b2tw2a.c3e.jpg)

I've been using that corner of the garage as a sort of dumping ground for 'stuff that looks useful', as in stuff that will never be useful, so I'll make a trip to the tip at some point. I'm also still considering getting rid of that sheet metal forge. Or at least cutting it into chunks that can be hidden under a bench somewhere.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 10, 2015, 12:40:12 PM
Drilled about 10 holes in a scrap of plywood trying to get one that's a good fit with these 47mm bearings. When I finally get one that seems good, I push the bearing in and then it falls out the other side. Turns out the hole cutter is cutting more of a cone shape.

I might maybe be able to take advantage of that, but I think I might try grinding the cutting tool to look more like what you get in commercial ones. As it is, it's still the shape of a lathe boring bar.
Title: Re: Drum/ Thickness Sander
Post by: awemawson on February 10, 2015, 02:13:48 PM
Can you cut your hole, slice across a diameter, then screw to a board making a sort of split housing with a tight fit ensured by the kerf of the cut.

Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 10, 2015, 06:07:02 PM
Can you cut your hole, slice across a diameter, then screw to a board making a sort of split housing with a tight fit ensured by the kerf of the cut.

That's not a bad idea. I'll have to think about how best to do it though.


(http://iforce.co.nz/i/hbfcwu3k.r4y.jpg)
Took the table apart again to hammer in one of these threaded inserts. These ones have barbs to hold the thing in, rather than a screw, so i'm putting them in from the other side.

(http://iforce.co.nz/i/25we0rgc.nis.jpg)
I added one more disk of 12mm plywood to make up the rest of the distance. Also screwed the ends on.

(http://iforce.co.nz/i/c0alxoxm.ixv.jpg)
Hopefully i'll get the drum round tomorrow. I'm wondering if maybe I should true the drum to the table (after rough turning) by passing a board with sandpaper on underneath it. The drum is wider than the table surface, but I could probably stick the board with sandpaper on it between some parallels.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 14, 2015, 12:04:21 PM
I've had a cold over the last few days so not much work done. Mostly because the wood dust was killing me. Excuses excuses.

(http://iforce.co.nz/i/tnf52h5z.k3b.jpg)
Figured out why the hole cutter cuts a tapered hole, the answer is pretty obvious; the adjustable bar just slightly rotates from the pressure of cutting. I cut a few trial holes to hopefully stop it from moving any further then cut the bearing hole. First one was a nice tight fit, but the second one wasn't so I expodied that bearing in.

(http://iforce.co.nz/i/lbu3ontc.h1t.jpg)
Don't have a good shot of the turning setup yet. I've changed it around after this photo since the motor runs clockwise.

(http://iforce.co.nz/i/wkkhq5dx.hbn.jpg)
I made a pulley for the 20mm shaft the hard way. Ideally i'd just use the lathe, but i'm trying to avoid it for this project, so I'm cutting it on the router table. The one on the motor should be less of a challenge.

(http://iforce.co.nz/i/yw0g3v04.qy5.jpg)
Used some wedged pieces nailed in to the board to get a close enough angle to match the pulley. It was still a ways off but hopefully it won't cause any trouble. If it does, i'll just cut it again on the lathe and lie about being successful with the router table!

(http://iforce.co.nz/i/xbp2cydu.wom.jpg)
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 18, 2015, 12:26:54 PM
Turned the drum round.
(http://iforce.co.nz/i/jxcdgf43.zjm.jpg)

Then removed one of the end pieces and cut a sector out of it. I cut my finger with a chisel fitting a door a few days ago, and it's one of those cuts that you just seem to bump on everything and keep re-opening.
(http://iforce.co.nz/i/gpxxvxya.q2b.jpg)

Then a trapezoidal block holds the paper in. As a part that will probably see a fair amount of use, a threaded insert would probably have been preferable here. But I suppose i'll replace it if or when the thread wears out.
(http://iforce.co.nz/i/xfbsdcm0.vkk.jpg)

With the paper wrapped around I was able to find where to cut the other sector out. Fortunately it landed in between the screw holes.
(http://iforce.co.nz/i/4zsvx5hz.aip.jpg)

No shots of it holding the paper on at both ends, since the first trapezoidal block split in half and is being glued back together. I'm using counter sunk screws in a countersunk hole, which wasn't a great idea. I've stuck a washer in the hole to hopefully stop it from wedging the part in half again.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on February 18, 2015, 10:01:12 PM
Simon, what about a simple temporary makeshift wood lathe for the pulley vee -- like you used for the sander drum.

I've actually done that with a piece of 1/2" pipe for an arbor, screwed into a 1/2" pipe floor flange as a faceplate. Attach your pulley blank to the floor flange with wood screws and turn the pulley true with an improvised tee rest and add vee groove using a chisel, or home made form tool.

You can run that arbor in wooden bearings for the temporary lathe setup. And lag it right to the benchtop for a temporary rig. Actually, oiled hardwood bearings work very well even long term if the speeds are reasonably low -- as wood lathe speeds are for this size work.

I mention this because, well, that router table rig does look scary the way you're using it, and also, not everybody has that tooling either.

Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 19, 2015, 08:48:36 AM
Simon, what about a simple temporary makeshift wood lathe for the pulley vee -- like you used for the sander drum.

I've actually done that with a piece of 1/2" pipe for an arbor, screwed into a 1/2" pipe floor flange as a faceplate. Attach your pulley blank to the floor flange with wood screws and turn the pulley true with an improvised tee rest and add vee groove using a chisel, or home made form tool.

You can run that arbor in wooden bearings for the temporary lathe setup. And lag it right to the benchtop for a temporary rig. Actually, oiled hardwood bearings work very well even long term if the speeds are reasonably low -- as wood lathe speeds are for this size work.

I mention this because, well, that router table rig does look scary the way you're using it, and also, not everybody has that tooling either.

I think my hands were fairly clear of the router bit, it was a tight fit around the spindle and didn't risk spinning freely, I wasn't climb milling, and I was taking small cuts with each pass. The biggest risk seemed to be the clamps holding the board to the table vibrating loose and allowing the thing to dig in. With the flat cuts I doubled up the clamps to reduce the risk, and with the groove the router bit had a bearing that would hopefully prevent total disaster if the clamps came loose.

(http://iforce.co.nz/i/gedeonbb.nzf.jpg)

There's alot of ways I could've cut the part. One idea was to cut a temporary pulley on the motor, drilling the 3/4" hole out to 20mm, and using the setup to cut the drum itself as a lathe (driven by the temporary pulley) to cut a nicer one. Although the only 20mm drill bit I had was a spade bit. A plug of wood could've filled the hole but it couldnt be cut with a hole saw/ hole cutter due to the hole in the middle. So careful work on a bandsaw cutting a tall but narrow 3/4" inch plug, which seems like a fairly dangerous thing to do.

But then another safety concern is using chisels to cut deep grooves. With chisels you don't get the leverage you would with real turning tools, and making fairly deep grooves seems like a bad idea with a chisel and I wouldn't want to do it more than once.

I still think, outside of using the metal lathe in any way, the router table was the most convenient and the safest way to cut the part I had available.
Title: Re: Drum/ Thickness Sander
Post by: RobWilson on February 20, 2015, 04:01:27 PM
Nice going Simon  :thumbup:  interesting design and very resourceful in its execution  :med:



Rob   
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 20, 2015, 04:25:40 PM
Nice going Simon  :thumbup:  interesting design and very resourceful in its execution  :med:



Rob

Thanks!

I did a bit more today and made the motor mount. The motor is extremely heavy and took some wrestling to get it into place. It's held on sideways so the capacitor doesn't foul the table above it.

(http://iforce.co.nz/i/hbrqlnhz.4xn.jpg)
(http://iforce.co.nz/i/p3wc3ekn.0wd.jpg)

Doubt that hinge would hold with it hanging from a V belt, so i'm probably going to put a block of wood under the motor mount once I figure out how big it'll need to be.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 21, 2015, 04:12:00 PM
My ever enlarging gut is in the majority of shots I take. It's like it's the star of the show.
(http://iforce.co.nz/i/yttsgfr2.evr.jpg)

More unflattering poses as I grind some sheet metal. I find it funny that i'm wearing alot of PPE and it looks over cautious. But problems in the past have proven that each item is necessary. Still didn't bother putting an apron on, even though i've set myself alight before.
(http://iforce.co.nz/i/dkblarmk.wcr.jpg)

These plates are to prevent wear on the wood when clamping the table.
(http://iforce.co.nz/i/acwxhbyx.n5d.jpg)

With the table now lockable, I could attach the bearing flanges to the sides. I was checking to make sure everything was square as I was going, and everything seems to be aligned (or close enough!).
(http://iforce.co.nz/i/fmmcpahy.zhn.jpg)

Unfortunately I can't hook the motor up at the moment since i'm waiting on some money to buy a belt. I think I'll start working on the dust hood next. But it's really nearing completion now.
Title: Re: Drum/ Thickness Sander
Post by: RobWilson on February 21, 2015, 04:16:02 PM
Thats a canny kite Simon  :lol: :lol:


What size belt do you need ,,,,,,,,,,,I possibly could have one that you could have   :coffee:



Rob
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 21, 2015, 04:50:05 PM
If i've calculated it right, an 884mm outside length belt or close enough should fit.
Title: Re: Drum/ Thickness Sander
Post by: RobWilson on February 21, 2015, 05:14:08 PM
I will have a look tomorrow  :thumbup:

Rob
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on February 21, 2015, 06:33:07 PM
Rob, have you gone up or down?  :)
Title: Re: Drum/ Thickness Sander
Post by: RobWilson on February 22, 2015, 02:41:40 AM
Rob, have you gone up or down?  :)

 :lol: :lol: :lol: Fooking up   :Doh:


Rob
Title: Re: Drum/ Thickness Sander
Post by: RobWilson on February 22, 2015, 01:10:50 PM
Hi Simon

The smallest I have at home is an SPA1000 ,  I will have a look at work tomorrow .


Rob
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 22, 2015, 03:34:06 PM
Hi Simon

The smallest I have at home is an SPA1000 ,  I will have a look at work tomorrow .


Rob

Thanks for looking. Don't worry about it too much though.

In all honesty I probably won't have a chance to visit in the next week or so since i'm on call for my grandparents. My grandma isn't doing so well.
Title: Re: Drum/ Thickness Sander
Post by: RobWilson on February 22, 2015, 04:09:52 PM
Sorry to here your Grandma is not doing to well  :( ,

 I would drop the belt off or stick it in the post .

Rob
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 23, 2015, 01:02:09 PM
If it's not too much of a hassle, i'd appreciate that. Should I PM you my address?
Title: Re: Drum/ Thickness Sander
Post by: RobWilson on February 23, 2015, 01:44:48 PM
Aye good Idea  :thumbup:


Rob
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 24, 2015, 12:21:14 PM
Started glueing together the dust shroud.

(http://iforce.co.nz/i/isoehmgq.rlg.jpg)
I didn't pick the best way to do it. Making a fixture would've been most sensible but I wanted to see if this way would work.

(http://iforce.co.nz/i/kngf43tq.zee.jpg)
Once it's dried I'll cut into it and glue some splines in place. It probably won't stay together for long as is.

In other news, I was looking at Matthias' website and saw this. http://woodgears.ca/sander/lucian.html

It's weird seeing a replica of something i've built. It's even weirder when the guy's done a better job at it than I did.
Title: Re: Drum/ Thickness Sander
Post by: dsquire on February 24, 2015, 01:50:00 PM
Started glueing together the dust shroud.

.
snip
.

In other news, I was looking at Matthias' website and saw this. http://woodgears.ca/sander/lucian.html

It's weird seeing a replica of something i've built. It's even weirder when the guy's done a better job at it than I did.

You are making a fine job of that sander. I followed the link to Matthias' website and there are a lot of good ideas in there for DIY woodworking machines. Thanks for sharing.  :D :D

Cheers  :beer:

Don

Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 25, 2015, 12:25:30 PM
You are making a fine job of that sander. I followed the link to Matthias' website and there are a lot of good ideas in there for DIY woodworking machines. Thanks for sharing.  :D :D

Cheers  :beer:

Don

Yeah that guy has a nice website. It was a huge breath of fresh air when I found it, since it's fairly down to earth compared to alot of woodworking stuff out there.

(http://iforce.co.nz/i/zfqmc422.xeb.jpg)
They say beauty is in the eye of the beholder...

I'd started figuring out how to try get the splines all nicely spaced and staggered with each row, and decided something along the lines of 'sod it' and just cut them in wherever. I'll sand it flat and fill any gaps with body filler, and hopefully nobody will know once it's painted.

Speaking of painting, i'm still thinking about when would be the best time to start painting it. I feel I should do it before I have the thing actually working, or i'll never want to disassemble it. I'm also nervous about paint making stuff stick and increasing the thickness of the wood to the point that things that are currently tight end up jamming. Maybe i'll just do a token effort and paint the outside.


Also my dad found this on the road and took it home. He saw a pizza paddle in it but i'm not so sure. But i've got no idea what it is. My best guess is it's something for beating out brush fires, but then how did it end up on a road. Does anyone know?
(http://iforce.co.nz/i/mhy32asq.nzd.jpg)
Title: Re: Drum/ Thickness Sander
Post by: awemawson on February 25, 2015, 01:01:46 PM
Why not use a wax finish - no significant thickness build up, and helps rather than hinders movement.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 25, 2015, 01:09:46 PM
Why not use a wax finish - no significant thickness build up, and helps rather than hinders movement.

That's a good idea for parts like the belt tracking adjustment. But for where the table contacts the frame, I kind of want that to grip a bit. As it is, it seems perfect.

Honestly, i'm not sure if it's necessary to paint stuff like this. It doesn't have to look good. But i'm only tempted to for the sake of the video. It might also help things stand out in the garage. In alot of shots i'm taking i'm noticing that stuff is blending into the background clutter.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on February 25, 2015, 01:15:41 PM
For the thinnest finish I'd use a clear brushing lacquer, first coat mixed with talcum powder. This makes a very easily sanded sanding sealer. Use 300 grit paper on that by hand and you can easily sand by hand right back to the wood grain. Do a second coat (they dry in minutes) and sand that back w/ 300 grit paper, and you're ready for a color coat (if you want one. In the U.S. Krylon standard spray cans are colored lacquer. So I use that for fine and thin finishes.

Lacquers are super thin, not like oil based paint, or acrylics, polyurethanes, or just about anything else.

If you do use wax, that may work, but be aware you won't be able to paint it if you change your mind. The only thing that removes wax is ammonia, and not if it is penetrated into the wood. Paint won't generally stick to waxed wood.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 25, 2015, 03:30:28 PM
Removed the table to put a bar across for the height adjusting screw to push against. I also found out that the motor gets in the way of the table when trying to remove it, so I had to take the spindle off. With it like that I thought I might as well paint it. The only paint I had that wasn't white was some purple emulsion. I don't think it'll do anything to seal the wood or protect it, but I figured that won't be a problem since I usually leave things bare.

(http://iforce.co.nz/i/2ieakuhd.3vx.jpg)

I think the lighter spots are just where the paint is still wet. At least I hope that's the case, since i'm out of paint.

I guess I'll try think of a good colour to go with the purple to paint all the furniture.

Also that talcum sanding sealer tip sounds good. I'll have to remember it for when I finally get around to making a banjo.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on February 25, 2015, 08:17:00 PM
re. talcum powder -- modern baby powder is often corn starch, now, which you definitely don't want for a sanding sealer. The type to use is the real talcum powder, which is made from talc.

I have only ever used it in lacquer, or on early model airplanes, "dope." Dope is actually lacquer of two different types, butyrate dope or nitrate dope.

Anyway the main thing to remember is lacquer and talc for a sanding sealer. It sands incredibly easily, and when sanding smells like baby powder. Not so nice when it first goes on, though. Lacquers require powerful thinners.

I don't have any experience in using any other vehicle with talcum powder than lacquer, and suspect the they would NOT work well at all. Lacquer dries very quickly and very hard and quite thin. Most enamels, varnishes, etc are the opposite of all of those traits, and would probably be  real mess.

The only exception I can think of is shellac (actually related to lacquer the lac in the name) that also dries fast thin and hard -- and is thinned with denatured alcohol. It  might work.....
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 25, 2015, 09:08:17 PM
I always thought when I got as far as needing to finish a banjo i'd be going with nitrocellulose lacquer. It seems like it's the easiest to work with from what i've read. The meranti i'm using has some pretty huge open pores so I figured a sealer would be necessary, but I find the world of finishing pretty complicated. Especially so when it's hard to get ahold of alot of things in the UK. So i'm liking the idea of only having to source one kind of lacquer.

Although one problem might be the talc being white. I wonder if any kind of dye/ pigment would work well mixed in..
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on February 25, 2015, 09:13:47 PM
Simon if you don't put too much in, and you sand it back, the talc becomes pretty much transparent, so you could bright finish it if you liked it with un-talcumed lacquer. Or if you wanted to transparent pigment it, most any aniline dye mixed with lacquer thinner would tint it to the degree you wanted.

If you want, try it on some scrap.

I use the sanding sealer on all of my casting patterns. In fact I just worked on my pulley pattern tonight and hit it with a coat.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 27, 2015, 03:08:11 PM
Simon if you don't put too much in, and you sand it back, the talc becomes pretty much transparent, so you could bright finish it if you liked it with un-talcumed lacquer. Or if you wanted to transparent pigment it, most any aniline dye mixed with lacquer thinner would tint it to the degree you wanted.

If you want, try it on some scrap.

I use the sanding sealer on all of my casting patterns. In fact I just worked on my pulley pattern tonight and hit it with a coat.

Yeah testing it sounds like a good idea. I've got plenty of meranti scraps hanging about.

Did some more on the sander.

Made the belt guard. I had this geet fancy thing planned with a nice but complicated shape, but decided I couldn't be bothered with all the angled cuts so I made this monstrosity. Needs tidying up after the glue dries.
(http://iforce.co.nz/i/fmegukdl.fcg.jpg)

Also got the thing re-assembled.
(http://iforce.co.nz/i/t3h32o4n.4xi.jpg)
Shame about the patchy paint, since I'm probably not going to give it a second coat.

I put a new (and longer) cable on the motor while it was all apart. I might redo it again though since i've just got the wires wrapped around the posts. Some crimp eyelets would probably be less likely to shake loose over time.

Also i've started making a list of what I should probably do after this thing is finished. First is to fix the bike and the ladder to the roof so I can get into the far corner, then get the dust collector finished (I was putting it off for the price of soil pipe fittings), then I really need to improve the lighting in the garage. I should probably also paint the roof white to try get some light reflecting.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on February 28, 2015, 11:54:25 AM
Rob Wilson popped in today with some belts and a bunch of other stuff, including break cleaner which is something i've been meaning to get for a while. Thanks Rob!

(http://iforce.co.nz/i/sdggogdu.y2m.jpg)
The belt is a bit smaller than the pulleys i'd made, but that gives me a chance to make some better pulleys out of aluminium.

So I got about 20 seconds into cutting off a chunk of aluminium with a dull hacksaw blade and decided to try clear the garage a bit instead.

(http://iforce.co.nz/i/edczk5rl.ek5.jpg)
I got the bike hung up in this corner. Doesn't give me alot of room for the step ladders. I suppose i'll try sort them out when one inevitably gets knocked down.

With the bike out the way, I could get into the corner by the doors and clear that up. It's still a bit messy but it's one hell of an improvement.
(http://iforce.co.nz/i/u1le32oo.to4.jpg)
(http://iforce.co.nz/i/tmnxnqqt.wn2.jpg)

The next corner to tackle will be this one on the other end. Also looking at this photo, I found my missing funnel. It was camouflaged in front of the red box..
(http://iforce.co.nz/i/spyj2uqp.v1v.jpg)

Then I need to sort out my basket of hardwood. It's difficult getting into this corner to sweep the dust up with it and the site lamp in the way. Hopefully better lights on the ceiling will remove the need to use that lamp when filming.
(http://iforce.co.nz/i/thg2hn4z.u1e.jpg)

I think tomorrow I'll try relocating the big ladder to the roof. With that off the wall I can then start working on finishing the dust collector.

The drum sander is close to completion but I want to have dust collection working before I start running it.
Title: Re: Drum/ Thickness Sander
Post by: RobWilson on February 28, 2015, 01:17:53 PM
Blood hell you have been busy Simon  :clap: :clap: :clap: so there was a floor in that corner of your shop  :lol:


I got to cast my eye over the sander today and its just as impressive in really life  :thumbup: its going to be a cracker when its fully up and running  :med:


Rob   
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 02, 2015, 09:57:28 AM
(http://iforce.co.nz/i/tlhbkoil.cuu.jpg)

I tried painting the ceiling and... well. I'm hopeful it'll help improve the lighting cuz it sure as hell hasn't made my garage any prettier. I've been shining the site lamp onto the ceiling and using the reflected light to light alot of my filming. I'm planning to get some more tube lights (the one thing B&Q seems to be good at is the price on tube lights. It's the same price as eBay at least) but chances are i'll still need to use the site lamp.

With the roof painted (or as much as I can be bothered to paint it) i'm gonna have a go at hanging the ladder on the roof next, but I need a break. Spent 3 hours walking around Consett (there's some good hardware stores in that town) and it's about the most exercise i've done all year. I felt I was forgetting something important the whole time I was there though, and I just realised what I'd forgotten; hacksaw blades.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 02, 2015, 12:20:42 PM
Got the ladder on the roof. The thing is alot heavier than it looks, I couldn't lift it all by myself. Had to rest one end on the floor and lift it up to a pair of hooks, then go through the house to get behind it and lift it up/ tie a rope around it. Then get up on the step ladder to screw the next pair of hooks in.  I decided to point the hooks towards each other so the only way to remove it is to remove the hooks. I didn't like the idea of inevitably bumping the thing and having it slide off the hooks and onto my head.

(http://iforce.co.nz/i/nbe1zcfv.0kr.jpg)

I also moved the tool chest Rob gave me (a year or so ago) to somewhere more convenient. In the far corner it was only being used for storing my rust collection. I'll probably move my drills and lathe tools to it at some point. I also need to get some wheels for the bigger bench grinder I bought at a boot sale last year. I'm also thinking about making a pedestal for it
(http://iforce.co.nz/i/n02gr3jw.2cc.jpg)

Despite all the work, the garage still looks a mess.
(http://iforce.co.nz/i/02q0ebp4.dly.jpg)
Title: Re: Drum/ Thickness Sander
Post by: RobWilson on March 02, 2015, 12:28:15 PM
Looks allot lighter   :thumbup:

Rob
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 04, 2015, 09:12:06 AM
(http://iforce.co.nz/i/nclzgvar.fe4.jpg)

Work on the dust collector. I'm not too happy with how it's attached to the wall though, the wall plugs pull out a bit if I pull on it lightly. Really I should probably take it down in case it slowly works its way loose.

I might try make some angled brackets to hold it on a bit more at the top or something.

But it does seem to be working (although light dust is making it through. I've got a filter bag to stick over the outlet to catch anything that makes it through). It's just clamped together and nothing is sealed so hopefully efficiency will improve.

I'm hesitating on glueing it together/ sealing it up because I've got that terrible feeling that i'm forgetting something important.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 04, 2015, 01:58:38 PM
(http://iforce.co.nz/i/avtgl0wn.k3x.jpg)
Glued the thing together and also attached the filter bag to the outlet.

Then with nothing else to do till I get some soil pipe fittings, I started hacksawing that aluminium bar. Got about a centimeter in when I had a different idea...
(http://iforce.co.nz/i/s24nyvff.v3c.jpg)
I used this circular saw I bought from aldi for cutting sheet steel a while ago. It's a fairly underpowered thing and stalls very easily (even when cutting things within the stated limits), but that turned out to be a good thing since it eliminated the risk of kickback. I was able to saw through the 64mm aluminium bar cutting from both sides.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on March 04, 2015, 08:45:44 PM
It feels good to attack a shop and get things the way you imagined they should be. Good on ye!  :thumbup:
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 05, 2015, 09:08:49 AM
It feels good to attack a shop and get things the way you imagined they should be. Good on ye!  :thumbup:

Yeah it does! It's also good to do stuff you don't have to think too hard about. The sander is one of those things where, if I let myself, i'd think about every minute problem to the point that I never make the thing. I've been lucky that stuff like the motor I wasn't planning to use just fit, as did the stock sanding belt I bought for the conveyor. It's the kind of thing I should've thought a bit about ahead of time.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 05, 2015, 05:15:37 PM
Made a pair pulleys. It took me all day to make both of these, most of the time was spent changing tools in the lathe. Some day i'll get a quick change toolpost and make that cam lock tailstock...

(http://iforce.co.nz/i/xmp0324s.xfk.jpg)

Got to try a couple of things i've been wanting to do for a while. First was using a reamer for the first time, at 3/4". And second was heating a thing up to fit it onto a spindle.

(http://iforce.co.nz/i/ybyld21k.gyu.jpg)

(http://iforce.co.nz/i/tgoxxkpf.qvc.jpg)

I'll have to wait for them to cool down to test them though. Hopefully I got them spaced right, or I'll have to use a puller to get them back off.

I'm really on the home stretch though. Tomorrow i'll sand the drum round and get the electronics properly hooked up. After that it's just getting and installing the windscreen wiper motor for the conveyor. If all goes well I could have the video made by Monday.
Title: Re: Drum/ Thickness Sander
Post by: micktoon on March 05, 2015, 06:44:22 PM
Hi Simon , nice job on the pulleys  :drool: :thumbup: as you say on the home stretch now, I look forward to seeing it in operation, keep up the good work  :dremel:

 Cheers Mick.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 06, 2015, 06:35:12 PM
Did a little thing today.

(http://iforce.co.nz/i/comxgphb.fij.jpg)

Height adjusting screw. I had a brain fart with it at first, intending the disk part to stay still vertically and push the threaded rod up, but I didn't consider that it'd just spin freely and not move. So there's a nut wedged into the wooden brace.

I had alot more planned today but I ended up working on the garage lights, since with them propped up against a wall I thought it was inevitable that i'd crash something into them.
Title: Re: Drum/ Thickness Sander
Post by: RobWilson on March 07, 2015, 03:43:51 AM
Nice job machining the pulleys Simon  :clap: :clap: :clap: :clap: :clap: :thumbup:

Must be really close now  :ddb:



Rob 
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 07, 2015, 11:37:20 AM
Nice job machining the pulleys Simon  :clap: :clap: :clap: :clap: :clap: :thumbup:

Must be really close now  :ddb:



Rob

Thanks!

I got the windscreen wiper motor today.

I also sanded the drum true. The thing is at its maximum capacity doing this, which isn't too thick. I suppose I could always change it if or when I need to sand something taller.
(http://iforce.co.nz/i/ovupjkh0.l1x.jpg)

Then I varnished the drums. Rob's suggestion was to hold the paper on with spray adhesive, and it sounds like a better idea than relying on just holding the ends. Hopefully the varnish will make it easier to remove/ clear the glue residue off.
(http://iforce.co.nz/i/cjp0xjos.wur.jpg)

Shame i've got to wait for the stuff to dry though. I've got a few things to do in the meantime at least.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on March 07, 2015, 11:56:08 AM
They make spray adhesive especaly for holding disks on automotive sponge rubber sanding disks. I used to use those when building stripper canoes. You have to play with how much to put on, and how long to wait for it to tack before sticking it together, and whether to spray both the drum and paper, or just one of them. So don't give up if it doesn't stick well or sticks too well and the sandpaper shreds when trying to remove it. Keep experimenting and you'll find a happy medium.
Title: Re: Drum/ Thickness Sander
Post by: Swarfing on March 07, 2015, 01:04:40 PM
I use 3M photo mount like a contact adhesive for my sanding blocks. It sticks firm enough to stay but not enough so you cant take it off easily.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 09, 2015, 03:56:05 PM
So much for a video today. I'm gonna pretend I meant next monday. I've mostly been waiting for that varnish to dry enough to sand. It's slow in the cold garage.

Yesterday I made a little box for the electronics, and got it hooked up and tested. Turns the motor/ adjusts the speed just fine but with a proper load and running for a long time, i'm not so sure how long that transistor will hold up in an enclosed box. Won't be hard to replace it and improve the cooling if that happens though.
(http://iforce.co.nz/i/fxfpdfau.ujc.jpg)

I spent most of today waiting for glue to dry, sticking two bits of oak together to make a block wide enough for part of the motor mount. It's clamped on here. Didn't get any glue squeezing out vertically so hopefully it wont seize the thing up.
(http://iforce.co.nz/i/jdqgqbm0.nqf.jpg)

I got to use the dust collector to suck up dust from the thickness planer today though. It's still not sealed up at all but it seems to be separating the dust fairly well. That said the planer produces mostly large chips and i'd imagine the thing would struggle more with the sander dust.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 11, 2015, 10:22:27 AM
(http://iforce.co.nz/i/tojebfqh.mqd.jpg)

Made a thing for locking the motor. It's cut down on vibrations but they're still there. It'd probably be a good idea to replace the cable ties with jubilee clips but that'd require taking the whole thing apart to get access. I'm not sure if I can be bothered at this point. I guess i'll wait and see how much of a problem the vibrations cause; i'm worried they might give the sanded wood an undulated surface.

It's kind of funny but I never get too excited about finishing projects. I think i've said it before but I started making videos partly as a motivator for finishing things.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 11, 2015, 02:57:29 PM
(http://iforce.co.nz/i/rxcyzy15.dhs.jpg)

Had the belt going for a bit and then the epoxy bond broke. I've been fussing most of the day trying different methods to couple the thing till I realised that garden hose has an internal diameter of about 12mm. There's a bit of bar threaded and screwed onto the end of the motor that's epoxied to the hose, and it's held on with a jubilee clip at the roller end. Life is hard without a lathe.

Anyways I kind of jumped the gun in trying it out, so i'm trying it again and letting the epoxy cure overnight. There's room in there to fit two jubilee clips but I'd have to head out and buy a second.

It's all these little things that seem to take the longest. Tomorrow i'll head out and buy another junction box (the one I bought I ended up using with the new lights) and get it neatly wired up. Then there's finishing off the dust hood and attaching the sandpaper to the drum and it should be complete.

I think for the last 10 or so posts in this thread i've been saying it's nearly complete but I think I really mean it this time.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on March 11, 2015, 04:28:04 PM
Take as long as it needs, Simon.  :thumbup:
Title: Re: Drum/ Thickness Sander
Post by: RobWilson on March 11, 2015, 05:04:06 PM
I have an Oldham coupling  going spare if you need it Simon .


Rob
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 11, 2015, 08:08:13 PM
I have an Oldham coupling  going spare if you need it Simon .


Rob

I think I'll be fine, but thanks for the offer. I want to try build this thing with as many easily available things as possible.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 13, 2015, 01:19:36 PM
(http://iforce.co.nz/i/2gbyckam.ljc.jpg)

It's finally done. Well maybe not finally but it's done enough to make a video.

I had an interesting problem where the off switch stopped working for the speed controller, and on investigation it turned out the little heat sink got so spicey that it melted the insulation on the two switch wires, which were touching it, and they shorted out. I guess the little box will need better cooling but i'll sort that out some other day.

Also the epoxy on the hose didn't hold up so I went with the double jubilee clips. In fact there were a whole bunch of problems, like the sandpaper not lining up when wrapping it on (which was simple to fix but required taking the drum off), and I managed to wire it up wrong the first time, so it's been a busy day.


(http://iforce.co.nz/i/rrda2fse.zdf.jpg)
I also had a kickback and was glad I'd decided to stand to the side of the thing because the block of wood really shot out. I guess the moral of that story is that if i'm going to sand small parts, I should secure them to a larger board first. I'm also kind of glad I caught this on camera though, even if it highlights my stupidity. Kickback is so mythical it's like getting a photo of bigfoot.

(http://iforce.co.nz/i/0hnzx3z2.enk.jpg)
It's left a fairly rough finish, which could be due to the 80 grit sandpaper, but i've seen on other people's sanders they like to use the velcro sandpaper. I imagine the soft cushion from that probably leads to a smoother finish. But the price of that sandpaper is insane.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on March 13, 2015, 02:11:53 PM
Congratulations Simon! :thumbup: :thumbup: :thumbup: :thumbup:
Looks like the video isn't quite up yet.

The sanding marks probably were from the coarse grit, though they aren't evenly distributed. Maybe there are ridges under or the paper isn't even?

Sanding semi cross grain as it looks like you did will definitely raise the grain much more than wth the grain.

I'm sure you'll work things out!  :clap: :clap: :clap: :beer:
Title: Re: Drum/ Thickness Sander
Post by: micktoon on March 13, 2015, 06:49:53 PM
Hi Simon , looks like you are making good progress in the right direction, just a case of ironing out the problem areas now hopefully. I bet you were glad that kick back did not hit you in the nuts mind  :bugeye:

  Cheers Mick.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on March 13, 2015, 08:04:32 PM
I had a wooden boat shop back in the 70's in a former mill with a bunch of other craftspeople. In a neigboring woodshop one of the employees, a woman, was ripping a board and holding with her hands while pushing it with her belly. A one inch by 6 foot strip of the rip waste broke off at a knot and the blade sent the piece right through her. They got her to the hospital in time and she survived,.

Kickback is real, and body position is extremely important to consider with woodworking machines.
Title: Re: Drum/ Thickness Sander
Post by: greenie on March 14, 2015, 03:22:25 AM
Good to see that you will be posting that piece of film showing the timber being kicked back out of the sander and sanding both sides of that bit of timber.

Apologies from those that said it wont happen, might be excepted. :doh:

80 grit is very severe on any surface finish, 120 grit will give it a far better finish, or if your after a good smooth finish, then 180 will be the grit you need.

So, are you going to fit any more rollers to the machine to add downward pressure to the timber on the movable belt to stop the kickback happening ?

Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 14, 2015, 10:41:20 AM
Good to see that you will be posting that piece of film showing the timber being kicked back out of the sander and sanding both sides of that bit of timber.

Apologies from those that said it wont happen, might be excepted. :doh:

80 grit is very severe on any surface finish, 120 grit will give it a far better finish, or if your after a good smooth finish, then 180 will be the grit you need.

So, are you going to fit any more rollers to the machine to add downward pressure to the timber on the movable belt to stop the kickback happening ?

That isn't what happened. The piece was just able to tip over, raising the back end into the drum, encouraging it to tip over further until the whole thing escaped with alot of momentum. At the time of it jamming the feed belt momentarily stopped moving, because there was alot of downwards force with the piece. I'm lucky it didn't tear the feed belt when it shot out. I'm also not sure if you're aware but the feed belt moves very slowly.

Anyways that small part would've probably done that feed belt or not. If i was standing behind the machine pushing it through like you suggested with some sticks then I would've been right in line to lose a few teeth.

As for the grit, yeah it's a given that a lighter grit would leave a smoother finish, but I went with the 80 since I want this machine to level wood fairly quickly more than produce a good surface. A regular bit of hand sanding and scraping would smooth out the surface quite easily.

And for the rollers, I did draw up a quick system for attaching some if necessary when thicknessing veneers (which may warp a fair bit after cutting), but for most stuff it's probably preferable if it isn't trying to be forced flat to the table.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 14, 2015, 07:45:18 PM
(http://iforce.co.nz/i/jvdgrmx0.3fn.jpg)

I hate editing audio. Had just under an hour of raw commentary to cut into clips. It's bad enough talking for an hour, but having to then listen to it all in detail is beyond tedious.

The funny thing is that despite all the effort, I still get alot of comments on my videos of people saying they can't understand me. Since I'm mostly reading from a script it wouldn't be too hard to add subtitles to the video, i'm just reluctant to do it since something doesn't feel right about subtitling yourself.

At least people assume i've got a Thick Accent, and don't realise that I really just talk like an idiot.

In other news, I had a go at sanding those hexagons I made a good few months ago. I'm going to pretend I left them that long to let the wood stabilize.
(http://iforce.co.nz/i/km15ezo3.jfm.jpg)

They came out nice and flat, which was good to see. Hopefully I won't get sidetracked again and manage to make a banjo after about 2 years since I started the project.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on March 14, 2015, 08:43:39 PM
I can understand you fine. Others need to learn. Don't make incapability easy for them, Simon. :beer:
Title: Re: Drum/ Thickness Sander
Post by: RobWilson on March 15, 2015, 05:38:36 AM
Good to see you have the sander up and running Simon  :clap: :clap: :clap: :clap: :clap:


Rob
Title: Re: Drum/ Thickness Sander
Post by: Meldonmech on March 15, 2015, 11:50:18 AM
 
   Hi Simon, were the problems on the speed controller, associated with the feed motor?

                                                                               Cheers David
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 15, 2015, 09:54:45 PM


About damn time.

I gotta be honest I didn't have alot of fun editing this one. Two months worth of big long boring video clips of me sawing stuff to sift through. It took me quite literally all day from 9 till now. I'm not a big fan of multi-part videos but if I ever end up doing a big project like this again, i'll probably go back to that format just to keep it manageable.
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on March 15, 2015, 10:17:21 PM
That was definitely worth the wait Simon!  :thumbup: :clap:
Title: Re: Drum/ Thickness Sander
Post by: dsquire on March 16, 2015, 12:10:14 AM
Simon

Like Steve said, "definitely worth the wait Simon! "

If there were a video of the month selection you would be my first choice. You probably spend as much time or more taking photos and editing them as you do making the drum sander.

Thanks so much for taking the time too do this and share this with the members.
:D :) :D

Cheers  :beer:

Don
Title: Re: Drum/ Thickness Sander
Post by: RussellT on March 16, 2015, 05:18:02 AM
I liked the video, and the machine.

Well done.

Russell
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 16, 2015, 09:10:44 AM
Thanks for the comments!

I forgot to add a thanks to Bluechip/ Dave in the video for helping out with the electronics. I added one to the video description.

There's probably some other people I aught to have thanked too but this project took so long my memory has gotten hazy.
Title: Re: Drum/ Thickness Sander
Post by: RobWilson on March 16, 2015, 10:58:52 AM
 :clap: :clap: :clap: :clap: :clap: :clap: Well done Simon , 


Looks like it works a charm  :dremel:


Rob
Title: Re: Drum/ Thickness Sander
Post by: NormanV on March 16, 2015, 11:58:03 AM
Excellent! Well done, and I could understand you.
Title: Re: Drum/ Thickness Sander
Post by: micktoon on March 16, 2015, 12:42:34 PM
Hi Simon, top marks for the sander and the video too, good editing and film work.Thanks for taking the time to record it all, it was a ig enough project to do without having to film it all too.

 Cheers Mick
Title: Re: Drum/ Thickness Sander
Post by: Bluechip on March 16, 2015, 04:32:30 PM
Thanks for the comments!

I forgot to add a thanks to Bluechip/ Dave in the video for helping out with the electronics. I added one to the video description.

There's probably some other people I aught to have thanked too but this project took so long my memory has gotten hazy.



All very nice to be publicly acknowledged, but where do I send the invoice ...  :lol:  :lol:  :lol:

Now, about your sizzling MOSFET. What is driving it ?? ie Where does the 12V come from?

If it is not too well regulated, the voltage may well be dropping when the motor is driven on under load. If this happens the drive to the MOSFET could be insufficient to switch it in a sharp fashion and it will run warmer than necessary.

Scope the supply and see.  :thumbup:

If it is, the quick and dirty way is to shove a diode in the supply to the '555 circuit ....

See attached:

If you do this the drive to the MOSFET gate should always be close to the full 12V and it will be driven on pretty damn quick, as the motor cannot drag the 12V to the '555 circuit down. C1 can only charge from the supply, it cannot discharge into the load, D1 prevents this.

This does assume that is the cause ... what MOSFET are you using anyway ??

Dave

PS C1 should be 220uF ...  :palm:

Title: Re: Drum/ Thickness Sander
Post by: Will_D on March 16, 2015, 04:47:17 PM
Many thanks for an excellent thread and brill. video. :mmr:



Title: Re: Drum/ Thickness Sander
Post by: millwright on March 16, 2015, 05:47:57 PM
well done Simon,

  I have followed and enjoyed the thread from the start. The icing on the cake must be the video and seeing it all come together. a great job.

                                                           :clap: :clap: :clap: :clap:

John
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 16, 2015, 06:01:49 PM
Thanks for the comments!

I forgot to add a thanks to Bluechip/ Dave in the video for helping out with the electronics. I added one to the video description.

There's probably some other people I aught to have thanked too but this project took so long my memory has gotten hazy.



All very nice to be publicly acknowledged, but where do I send the invoice ...  :lol:  :lol:  :lol:

Now, about your sizzling MOSFET. What is driving it ?? ie Where does the 12V come from?

If it is not too well regulated, the voltage may well be dropping when the motor is driven on under load. If this happens the drive to the MOSFET could be insufficient to switch it in a sharp fashion and it will run warmer than necessary.

Scope the supply and see.  :thumbup:

If it is, the quick and dirty way is to shove a diode in the supply to the '555 circuit ....

See attached:

If you do this the drive to the MOSFET gate should always be close to the full 12V and it will be driven on pretty damn quick, as the motor cannot drag the 12V to the '555 circuit down. C1 can only charge from the supply, it cannot discharge into the load, D1 prevents this.

This does assume that is the cause ... what MOSFET are you using anyway ??

Dave

PS C1 should be 220uF ...  :palm:

That's a clever solution. Although to be honest i'm really sick of this project at this point. I'll save all this for when the thing fails. Thanks for it though.
Title: Re: Drum/ Thickness Sander
Post by: S. Heslop on March 16, 2015, 06:11:58 PM
well done Simon,

  I have followed and enjoyed the thread from the start. The icing on the cake must be the video and seeing it all come together. a great job.

                                                           :clap: :clap: :clap: :clap:

John

It was quite nice waking up to a bunch of comments saying I did a good job! I wasn't so enthusiastic about the video when going to sleep, and I still feel like I could've done a bit better in parts.

I'm interested to see how many views this video gets. My spindle sander vid got a huge amount and really surprised me, and I guess through arrogance i'm thinking that maybe this video could perform similarly. It's bottling lightning though.

Title: Re: Drum/ Thickness Sander
Post by: JD on March 16, 2015, 06:44:24 PM
Simon, cracking project I have enjoyed it from the start. The combination of your photos and video editing make this an enjoyable thread to follow. Well done.
John W
Title: Re: Drum/ Thickness Sander
Post by: vtsteam on March 16, 2015, 09:44:37 PM
My spindle sander vid got a huge amount and really surprised me, and I guess through arrogance i'm thinking that maybe this video could perform similarly. It's bottling lightning though.

It isn't arrogance, Simon.

 :beer:
Title: Re: Drum/ Thickness Sander
Post by: tom osselton on March 17, 2015, 05:27:54 PM
I enjoyed seeing it come to life along with the pitfalls you encountered so well done and that was a nice video too!