Making a belt sander..

[NeoTech]

Well.. I havent got the images from when i welded the frame, but the frame consists of 3m 40x40x4mm, SS235 mild steel.

Most other stuff on this project is scrap.. bits and pieces of stuff i have lying around..

Made the first idler:
i had a piece of 240x110mm 6068-T6 aluminium - this will make up most of the wheels, for smaller contact wheels i have some 7075-T?

Then i made the tracking mechanism

The idler is fitted with 22mm skateboard bearings, and a 12mm stainless rod was turned down to 8mm and threaded with m5/0.8mm and a small "cap" was turned so the idles stays on the axle.
The mechanism is made of.. well bits and pieces of steel a nut welded to the frame and a 1/2" bolt. ;)

then i needed an axle for the drivewheel.
i had this 500mm stainless rod in 25mm OD, some  unknown stainless but turned really good.
the flange bearings i got from some other old machine i took apart hade a ID of 20mm so the axles was turned, 18mm, 20mm, left 25mm, 18mm.. the 18mm parts is for the drive wheel and later
on the pulleys.

and here is the whole thing somewhat assembled/mocked up so i could determine if the wheel would align.. they wouldnt so spacers in aluminium rod was made and the stainless axle was threaded M8 in the ends to the spacers would double as a compression ring, they are turned sligtly with an angle so when i torque down on the M8 bolts.. the wheel friction stick to the axle.. =)


This is how far ive got.. This has taken me.. uhm 3 weekends so far..9 days...

And yeah the spring.. is a boat spring for anchoring boats.. its supposed to take care of a 600kg boat, but well i can compress it by hand so. will suffice. =)

[Rob.Wilson]

Hi Andreas

  CRACKING project    did you design it or are you working form someone else's  drawings ?

Rob

[NeoTech]

I more or less work out of my head.. i have seen similar designs been done of others.. From that i just.. well pick something up and started putting it together, made up the dimensions as i went along. =)

[Rob.Wilson]

I more or less work out of my head.. i have seen similar designs been done of others.. From that i just.. well pick something up and started putting it together, made up the dimensions as i went along. =)

  way to go    how long is the belt ? 

Rob

[NeoTech]

its made around a 5x72 belt, or a 50x2000mm belt depending. The idea is to have exchangeable toolposts, that can slide so you can accomodate more than one type of belt.. its actually next thing to build, tool post and motor mount is what is left. =)

[Rob.Wilson]

Do you have a specific use for the for building the machine or is it just for general linishing ?

I have often thought about building a smaller bench mounted machine 


Rob

[NeoTech]

i'm building it on a floor stand, cause i will use it for notching pipes, deburring in general and sharpening stuff.. But mainly nothing tubes.. i build rollcages for friends amongst other things, racecars, rally and so on. And well you make a toolpost with a piece of pipe you use for the cage, and that way you get the profile.. then you clamp some pieces of metall to it in the correct angle and just press the end of the tube agains the profile and voila.. perfect notch.
60-80 grit is prefered.

[NeoTech]

So this is how the smaller rollers for the platten came out. its 40 OD 7075-T6, this stuff cuts like if its stainless. But not with the heat.. Finish is.. well awsome. toolmarks from jaws though.. and sanding this was out of the question. Skateboard bearings here once more. this time i made the ID so i needed to tap the bearings in place with a plastic mallet.. better than shimming with papers like on the large idler.

[NeoTech]

Mhm, well it kinda works anyway.. i need to make a tool rest, a backplate for the front part, and readress some tracking issues its having at the moment..

[Noitoen]

Hi,

Great project. I would exchange the spring with a small motorcycle spring loaded shock-absorber. This should dampen the vibrations on the belt.

[NeoTech]

Ah the purpose of the spring isnt to dampen the vibrations, its to tension the belt actually.. The vibrations came off that i got the driveshaft sliiightl off, a halv a milimeter or so and that translates to like 2-3mm with the drive wheel on there..  But it could be countered by putting some force in the spring.. (long bar, me compressing it) that took out most of the belt vibrations..

But that damn tracking wheel doesnt do its job properly belt is all over the place, and different belts act differently.. strange actually. So need to weld a t-bar to that bolt so it will be easier to adjust.

[loply]

Hard to tell from the photos, but does your tracking wheel have a crown on it? It needs one in order to do it's job properly, else the belt won't self-center.

[doubleboost]

Hi
That looks to be a very handy bit of kit
I have done a bit of tube notching (die drinder)
Tour machine will make the job quick and easy (perfect result as well)
John

[NeoTech]

Yeah i have a 2 degree taper on the tracking wheel, but it will need plenty more to work well.

Pointers for making this yourself.
1) Belt tension, belt tension, belt tension.. The damn belts need to be like a frickin bowstring.
2) Crown tracking wheel.. dont be shy.. i was i have recut the wheel twice.. i'm on a 5-2-flat-2-5 now, it still dont track properly, blend blend blend with a file..
3) Make the tool arm adjustable.. it will help when you wanna swap belts.. And will help with belt tension.
4) Skateboard bearings are cheap, and they work great.. dont go for ABEC-7, they die instantly, but ABEC-5 worked like a charm.
5) Coverplate for the belt from the motor.. if... or when the belt decides to skip, it comes at ya, and it frickin hurt to get slapped in the face. ;D

I welded the frame, box for holding the bearings and such.. but in hindsight i should have bolted everything - it would been easier to adjust. Welding is faster though.

Whats left to be done is a backingplate for the belt, a toolrest and a tubing tool - that i make out of the very same tube i will need to cut. - will come back later with this when its somewhat done.

[krv3000]

ooo i like it

[NeoTech]

And well now i will say its "done" improvements will be made.. like making the belt track properly..  And make the drive wheel stop wobble sideways, making the belt track in and out a couple of mm. Its not perfect.. But this is my first "from start to finish no plans" - project.. im happy with it. =)



And here is a small axhead i ground on it. Using a 60 grit belt.

[DaveH]

NeoTech,
You did a good job,  looks good to me 
 
DaveH

[Stilldrillin]

But this is my first "from start to finish no plans" - project.. im happy with it. =)

Hmmm...... Yes!

I'd be happy with it, too! 

Well done! 

David D