Modifying a Grizzly 9 X 19 (G4000)

[Bernd]

  Well it's struck again.   

Must be the heat I guess, but I've started another project.

I think I've discovered that if I work on more than one project I can switch off and work on the other while either waiting to have an idea pop up, waiting for materials or just plain tired of working on this one and go to the other. I can probably get them done. So this is an experiment, sort of.

Anyway on with the project. I'm going to call this part "The Disassembly of the G4000". I have had the Grizzly 9 X 19 lathe for over 12 years now. It was ok to turn some round stuff but it never really work right from day one. Then John (Bogstandard) wrote a post on fixing Darren's lathe which is similar to the Grizzly and I knew I had to do it. Plus I want to make some chances that "may" radically change this lathe. You'll just have to be patient to see what happens. This is going to take a while.

First here is a picture of the lathe without tailstock. I forgot I should have taken a picture with it on. But you know what it looks like right?



First thing I did was to remove the lead screw. There is a split pin holding the lead screw on to the shaft of the quick change gear box.



At the other end are two screws that need to be remove to take of the support.



And there they are, lead screw and rear support for the lead screw.



That leaves the saddle free to be slide off of the ways toward the tailstock end.



And there it is on the ways. Not a good idea, but it was heavy and I needed to set it down in the only clean area I had.



Here's a look at the back of the saddle. Remember it's upside down. On the right is the two half nuts for cutting threads. Just to the left of that is where the worm gear was to drive the carriage. It fell out, plus I forgot to put it back for the pic.



Next to come off is the quick change gear box. Three screws and two dowels hold it on. A bit of prying with a screw drive had it loose in no time.



Three screws inside the box hold the box to the machine.



This is the back plate that holds the driven pulley from the motor and belt tensioner.



Here's the back of the lathe were the belt tensioner was.



Four screws remove the electrical plate so you can get at the three screws that hold on the whole box. You did remember to unplug the machine right?



I laid the headstock and ways on their side to facilitate the removal of the motor.



Now for the four screws that hold the headstock to the ways. You'll find the front two under the feed rate/ thread plate. The other two are revealed when you take the motor off.



And here's what it looks like with the headstock off the machine.



This is where I'm going to leave the project for now.



I need to get a side cutting mill and an arbor for the mill. Unfortunately I have the Kwik Switch 40 spindle. You'll find a description of it on my post when I moved the mill into the basement.

Don't hold your breath for the next installment. You'll turn blue and pass out. It'll be a while before the next adventure begins, Modifying the base.

Bernd

[Gerhard Olivier]

Youre a brave man Bernd

This is worth waiting for Mod to tools get me every time


Please put in lots of little detail and lots of pics of all steps -

Gerhard

[bogstandard]

Bernd,

Because you are only removing a very small amount of material from under the casting face, there is no need to go buying an expensive side and face cutter.

You can use what you already have, a flycutter. You will need to grind the faces to cut in the opposite direction. See attached C-o-C.

The most important thing when doing the job is to make sure the feet are clean underneath and the top faces of the ways are set up perfectly level to the bed, a DTI in your chuck and sweep the whole length of the casting. Shim up under the feet if you have to, to get it perfectly level. If it is a good topgrind and no shims are needed, then just a good table cleandown between swapping the casting around will be fine, otherwise, if shims are used, then for the second sweep after moving the casting, you will have to use a mag base on the head to get it level, as you cannot move the cutter.

Once you have the cutter set to depth, the table and quill is locked up rigid in the Z axis, and the casting manouvered around the cutter for doing both sides.


Bogs

[Bernd]

Bogs,

Thanks for that. I never would have thought of using a fly cutter upside down. Ingenious. Thanks much again, you saved me about $50 USD for the cutter and who knows how much for an arbor to hold it.

Were do I send the donations to? 

First I need to find that thread you did and reread it on how I go about this.

Pics and detailed info will be posted Gerhard.

Bernd

[Bernd]

Bogs,

Just did a quick check of the base ways. I checked them just like you showed. I find about .0015 variance on the back side and about the same on the front.

Think I still should go through and mill them anyway?

For those of you who have joined recently and wonder what this is all about, check out this thread that John did on fixing Darren's lathe bed. CLICK HERE

Bernd

Edit: Just rescanned that thread and I think I answered my own question. I'm going to go for it and check it all out anyway and maybe touch up the bottom of the ways.

[Darren]

Bernd,

If it helps I can tell you that with no doubts what-so-ever the work Bogs did to my lathe turned it from a pile of junk to one very nice and precise little lathe.
(it really was junk as nothing precise could be produced with it. I've said this before but I'll say it again. Mine was so bad I bought another lathe and used the mini as a bench polisher.....)

I'd say go for it if you have the confidence, as any and all improvements can only help.....


On another note, I don't know if you remember me making a new crosslide screw and nut for my Smart & Brown lathe? I never mentioned the results did I?

The crosslide was kinda rough feeling, the screw was well worn and the finish was nothing to shout about but ok ish.
Now since the mod the crosslide is as smooth as silk and the finish is superb. Far exceeded my expectations on all counts.

[Bernd]

Darren,

As you know I also have a 10" Logan lathe. This is were the main turning is done.

When I purchased this lathe they were not making very good lathes back then. I'm sure their (Grizzly) quality has improved because they are still around and have increased the types of machines they sell.

As far as this lathe is concerned it is a piece of poor quality. I could never single point a thread on this lathe and I knew how to do that. When I took the lead screw off I measured the lead screw threads. 16 threads per inch. Just like the Grizzly mini-mill or X-2. No wonder I couldn't thread properly. When finished with this project I won't be able to thread on it. Realy no need since I have the Logan. I'm going to change the lead screw to just a plain drive shaft with a keyway in it to drive the carriage via a DC drive. I'm also going to eliminate all the gearing and the motor. I'm going to use a tread mill motor and multi step pulleys. I'm also going to modify it so I can mount the head from my Sherline lathe on the cross slide. Plus I'm going to add some kind of spindle indexing so I can cross drill holes using the Sherline headstock.

This lathe is not going to look like it did before I had taken it apart.

Bogs,

I did a quick rocking check on the base. It rocks quite a bit. I'm going to mill the bottom of the base. Reason being is that I have something large to bolt this whole machine down to. Don't want to reveal that portion just yet. Let's just say it's cast iron and probably weighs 2 to 3 times as much as the machine.

You'd be proud of me since it is sort of your way of salvaging things and reusing them.

Bernd

[Bernd]

Time to bring this project back to some were near the top.

After I had set the lathe bed on the mill table to check the ways I noticed that it rocked. Not a good sign. That meant that the mounting surface of the bed wasn't flat. So I flipped the bed over and set it up on two 1-2-3 blocks and a couple of round ground 1" blocks. Now that the bed was sitting on the flat part of the ways there was no rocking. A good sign meaning that the ways were flat. All I needed to do now is take a smal bit of stock off the top to make the bottom flat.

Here's how I did it. I mounted the base upside down on the flat ways and very lightly strapped it down to avoid any twisting. Then a fly cutter was used to just clean up the bottom.



When that was finished I flipped the bed on it's mounting surface and I had no rocking. Very good.

Now I want to mount this on a solid surface so it won't twist. I had scrapped out a mill but had kept several parts from it. One being the table. This is were that table came from. It's down at the bottom of the pic.



There was a bit of surface rust on the table, but a quick sanding job with an orbital sander and it's good enough. I'll have to run a file over it as it does have a few large hickeys on it.



I was orignally going to mount the bed close to the front edge of the table but there would have been very little support under the feet of the bed toward the front, so it's going to get mounted in the middle as the picture shows.



And that's were the project sits for now.

Next will be the milling of the underside of the ways for the gibs.

Bernd

[bogstandard]

Very nice indeed Bernd, that lathe is going nowhere.

Seeing as you are making a very basic turning machine out of it, have you thought of using it for doing some small metal spinning and hand graving? All you would need to do is weld up a couple of rests that bolt onto the bed top.

Bogs

[Bernd]

I'm going to add an indexing mechanism to it. I'm also going to add a table that will allow me to bolt my Sherline mill column to the cross slide for cross drilling holes. Also going to make a grinder for it to use as a cylindrical grinder. These are only some off the mods that I've come across so far. Now it looks like I'll be adding metal spinning and hand graving to the list.

I'm still interested in making a aeophile steam engine and metal spinning would be easy to do. Also have never given hand graving a try. That'll be a new experince to add to the kit.

I know that using a grinder on a lathe is a big no-no but I have an idea that might keep a majority of the grit off the lathe.

Now that the major summer holidays and just about summer (lawn mowing) is over with, my projects can be worked on again with some semblance of order.

Bernd

[bogstandard]

Bernd,

Grinding on a lathe is one of those controversial subjects where people have a lot of myths, phobias and conjecture. Passed along by old wives tales and people with nothing better to do.

I personally think tales are spread because the people haven't had the know how or courage to try it for themselves, and so come up with all sorts of arguments for not doing it. Once you get into it, you will realise it is just another, although a slightly different machining technique, that once you have learned how to do it correctly, you will come back to doing time and again.

I have been doing toolpost grinding as long as I have been machining, and I have yet to see a machine with any of the symptoms it is supposed to create that weren't caused by natural wear and tear on a well used machine.
 
If you take the time to catch the majority of the dust, do a good clean down afterwards and keep your machine well lubricated, I will guarantee your bed won't fall in half overnight as some people seem to think will happen.

It is no more dangerous to your machine than hard skin dust off cast iron or turning any glass filled plastics, which in my mind will cause a lot more damage than grinding dust.

John

[Bernd]

John,

Back when I was working for the company they had many style grinding machines. So I've seen my share of different kinds of grinding form spindle noses to tapered bores. From standard cylidrical grinders to flat material grinders. The one thing I've never seen done in home work shop is when it comes to grinding is using a vacunm system. Although a bit dangerous of you suck in a lite spark since it'll set the rest of the swarf on fire. I've got some ideas furmenting in the back of my mind. I hope to try it out on this project.

And of course the old cover all the ways trick is helpful to.

I hope to see some progress on this project in the next few weeks. But first I need to reread your thread on Darren's lathe. I don't think I'll post a blow by blow buld since you've already done that. Think I'll just highlight perhaps what I needed to do different to make things work. I'll reference my writing back to that thread.

Bernd

[Darren]

Why don't grinding machines fail early if it's a problem?

You may reply that the ways are covered, but have you ever notice where grinding dust gets to in the workshop?

Everywhere, like sand on a beach....

[Bernd]

I was going to get started again with the Grizzly lathe project I had started back in September. I was going to start making the gibs for the carriage. But after close inspection on the bottom of the carriage, especially were the surfaces rub on the ways, I need to make a decision as to weather I should leave it as is or try to clean up the bad machining job that was done on this part.

First an over view of the whole bottom of the carriage. The V groove that is to the left is the front on the carriage. The flat surface is toward the back. Notice how rough the flat part is and the shiny marks were the carriage rides on the ways of the lathe. You'll also notice two dark lines on either side of the V groove in the lower left of the picture. These are the contact points between the carriage and the ways.




Here are two close ups of the flat way on the carriage. The first is of the whole length. The second is a close up of just one section showing the bright line of wear and the circular lines of the cutter.






The last picture is of the V way showing the shiny area which is in contact with the V of the way on the bed. Notice how uneven the wear is and the lousy finish on a surface that rubs on the V of the bed?




Now my dilemma is, should I leave the bottom of the ways alone or should I try and machine them to some form of smoothness. I haven't checked to see if the V way is a true 90 degree angle. The worst I can do is totally screw it up and I'll have to throw the carriage away. I can leave it alone, or I could get lucky and do a good job of fixing it.

I look to the membership for suggestions. Bog's what do you think. Can it be saved or should I use it as is?

Bernd

[andyf]

Bernd, you might find a bit of help and encouragement here:
 http://www.fignoggle.com/machines/7x12lathe/kahale-martinapmachine-7x12/lathe1.htm
which is a write-up (never finished) by Marty Nissen on how he sorted out all the sliding surfaces on a 7x12. Some of the pix are a bit mixed up with the text, but you will get the general idea.
Jose Meneses in Portugal picked up the baton and ran with it:
 http://www.toolsandmods.com/saddle.html
In each case, hours of hand work seem to be involved, to keep you warm during the long winter months.

Andy
 

[Bernd]

Andy,

Thanks for the links. I did a quick scan of them and will read up later. Looks like another alternative. I'm also thinking of possibly hand scrapping. My main concern is making sure that it it stays square and level through out the whole procedure.

Bernd

[Darren]

It would be nice to learn how to hand scrape, though I imagine a touch tedious 

[Bernd]

Daren,

My dad did a lot of hand scrapping. He even showed me how to do round pieces. Now that's interesting. The place I work at, on the assembly floor of the shop, a lot of scraping was done. So I know how it's done and some of the secreates behind it. I just haven't done it myself. And it's very labor intensive.

Bernd

[bogstandard]

Bernd,

I can only give you a personal view on this as the descision has to be yours.

If there are no areas along the length of all ways that have gaps (it shows as a complete stripe), then I would leave it as it is.

The machine marks are maybe less than 0.001" deep, and although it looks a lot, it most probably isn't.

When you have a perfectly hand scraped bed, you are not looking at a flat surface, but one covered in man made craters with the opposing surface running on the tops of the crater holes. The holes serve a purpose, and that is to hold lubrication, like tiny oil reservoirs all over the place. In my mind, your rough surface will do the same job.

That is just my way of thinking.


John

[Bernd]

John,

I've done some more checking. I'll post pics later. Those marks are as deep as craters. I think they machined these parts right after taking them out of the mold. I've decided I need to try and machine the surface that the cariage slides on. I'll post my thoughts about it with in the next couple of days. Thanks for the input.

Bernd

[Bernd]

After much contemplation and checking with an indicator I've decided that the best thing to do is to machine the surfaces of the carriage that ride on the bed ways.

First I needed to find a nice flat surface on the carriage to mount on the mill table. My first thought was to use my two 1-2-3 blocks. This turned out to be  a not very ridged set up. The surfaces that need machining were unsupported. So I thought why not use the cross slide table since the Grizzly's table is nice and flat. I had thought it would be flat, NOT. When I placed the cross slide with the face that is used to mount the compound slide on the surface plate it rocked. Now what? I turned it over and tried the surface that actually rides on the carriage. No rocking. So of I went to the surface grinder to remove that rocking. The first pic shows were the wheel started just skimming the surface. Lower left. The darker part of the pic.



After removing just .002" (.05 mm) this is what the surface started to look like. Not very flat.



It took another .004" (.1 mm) or a total of .006" (.15 mm) to clean up the whole surface. BTW that is the top were the compound slide bolts to. I then flipped the cross slide over and clean up the other side. Now the cross slide table would at least be flat and parallel. A quick check with an indicator on the surface plate that to be true.

Nice I placed the carriage on the cross slide table and started to check the contact surfaces of the flat carriage way. Note that the indicator is set at "0".



Next I moved it across the way. It shows a drop of -0.010" (.25 mm) in that small area.



Next I moved it all the way to the end of the flat way and got a reading 0f 0.008" (.2 mm) A difference of  0.018" (.46 mm) from the second reading.



Next I wondered if the V way was actually a 90 degree. I checked that with a small Vee Block I have. The bed V checked out not to bad.



The machined V in the carriage was another matter.



Stay tuned as I figure out how I'm going to machine these surfaces. A bit more thinking and studying the problem is needed first.

Bernd

[bogstandard]

Bernd,

It is a shame you don't live a little closer, as I have a large 90 deg milling cutter that would have done that easily. You could use a 90 deg countersink but I don't think it would leave a good surface finish.
Or mount the whole job at 45 degs and use a standard end mill.

The way to get a superb finish is to use your surface grinder. Mount the part up at 45 degs, gently scoop a bit out of your wheel sidewall to a width just slightly wider than the depth of the face you will be cutting.

See attached C-o-C


Bogs

[sbwhart]

Bernd

If you set it up in a horizontal mill, as for John's grinding set up you could then run a side and face mill down it.

Hope this helps

Stew

[bogstandard]

Just getting back to your problems Bernd.

These are the sorts of issues I was finding when I tackled Darrens lathe, so expect to find a few more little surprises yet.

It will be a matter of getting one bit done, then finding something else. You will have to call it a day at some point, otherwise you are going to end up with a lathe that will be too good for the work you have in mind for it.

Then you will have to find another to modify, and you will find something wrong with that one, and it goes on and on and on.....................................................


John

[Bernd]

Bog's

I wish I lived closer to you too. I sure think I would learn a few more things from you. Unfortunately they put a lot of water and distance between us. I have also given much thought to all the suggestion you have given here.

Yes a 90 degree milling cutter would be the thing to use on that V. If I only had a horizontal mill or a 90 degree attachment. But a visit to your shop to have you run it through your machine would surely be enjoyable visit.

I do wish I could set up the grinder to grind that out. I just don't have the tooling to do that right at the moment unfortunately. And what your saying about were am I going to stop with mods is kind of like doing a bathroom remodel. Before you know it you've got the whole house torn apart. Ask me how I know that.

You have to remember I've had this lathe for close to 10 years and Grizzly's quality control wasn't that great back then. It's a wonder it even cut stock off a part. I know it won't cut threads worth a darn.

Here's what I plan on doing. I'm going to mount it on the Bridgey table. Indicate it in. Then I'm going to mill the two surfaces. The flat with an end mill to get that warp out of it. I'm going to try with an end mill with a 90 degree end on it to clean up the V grove very very carefuly.

Then I'm going to try something that I've never seen mentioned on any of the metal working forums. This is a process that used to be done at the place I worked. I'm going to "try" and glue "turcite" on the machined surfaces. This was a material that was glued on the ways of the equipment we built. I'll take some pics of it later and post it. Very interesting material. First I need to contact an old friend at work and see if I can find out what kind of adhesive was used to attach the material.

My biggest fear about doing this is to get the cariage to sit level once I'm done with the machining. Believe me I'm not going to look any further for problems on the cross slide once this part is done. I look at it this way. I don't think I'll be off any worse than when I started.

This will take some time and careful maching. More later.

Guess I won't need to contact my friend after all. Just did a google and look what showed up. Turcite - B Slydway and what adhesive is used.

So I guess it's onward with the project. I'll keep posting updates as they become available.

Bernd