# Atlas TH42, My rebuild thread.



## Phonnold (Nov 23, 2013)

So I picked up a Atlas 10" lathe (I think), TH42 according to the model plate on the end of it.  It seem to be a good machine over all, just needs a good cleaning.  Things like metal chips in some of the bigger oil points and gunk and grim over it all.  So before I start using it I decided to tear it down, clean it and get it built back up and oiled.  Figured this way I will know the machine a little better and know that it is safe to use.  Here are some pictures of the lathe as I got it.







Tailstock isn't showing on the lathe as I have already taken it apart and done a good cleaning on it.  Here is the tailstocks condition before I prepped it and also after it was cleaned and primed, ready to paint.





Working on the compound slide now.  Have it apart and ready to be cleaned and primed.




Still no idea at this point what color I am going to paint it.  Picked up a Hammered Pewter color, but not committed to that just yet.  The lathe seems to have been a dark green as original color so maybe back to that.  I like the idea of a dark blue though for some reason.  I think if I could get a Hammered Navy Blue I would go with that, but I don't see that as a option.  Getting cold around here so not going to be able to paint that often, so have time to make up my mind.  Need to get a few ready and then get the torpedo heater going and warm up the garage enough for painting for a couple hours.

More updates as I get more done.

Philip


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## drs23 (Nov 23, 2013)

Looking good. Keep us posted.

Your chuck looks fresh. Don't see any battle scars.


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## stevecmo (Nov 23, 2013)

Philip,

Looks like a keeper!  Nice score!

I have the same paint dilemma with the Atlas shaper I'm working on.  I used Smoke Gray on my lathe and mill but thinking of going with more of a blue gray to more match the original Atlas color.  I bought a small can of black and blue to mix with the gray.  We'll see what I can come up with.

Good luck on your resto!

Steve


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## schor (Nov 23, 2013)

Nice find. I have a th54 and it was in worse shape that yours, Too busy using it to pull it apart to restore.

I've used this color on my drill press and various opther machines and I really like it and it holds up well. It's a wheel pain from duplicolor.


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## pipehack (Nov 24, 2013)

Phonnold- Nice lathe and it's starting to look good. Keep us posted.

Schor- That's a beauty. You did an awesome job. That graphite color looks fantastic!


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## mattthemuppet2 (Nov 24, 2013)

great score and looks in pretty decent condition already. Looking forward to the rest of the rebuild. If you don't mind me asking, how much did you pay for it? I'm building up a mental picture of good prices for this size lathe for when I might be able to buy one in a year's time or so.


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## Phonnold (Nov 24, 2013)

schor said:


> Nice find. I have a th54 and it was in worse shape that yours, Too busy using it to pull it apart to restore.
> 
> I've used this color on my drill press and various opther machines and I really like it and it holds up well. It's a wheel pain from duplicolor.



schor, what color is that?  That looks good.


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## schor (Nov 24, 2013)

Phonnold said:


> schor, what color is that?  That looks good.



Duplicolor 'graphite' wheel paint. I've put cutting fluid, coolant, whatever on it and it holds up. I have a test area on my lathe that is always getting splashed and no paint is coming up.

The press has the clearcoat version of the paint for final 2 coats.


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## Phonnold (Nov 25, 2013)

mattthemuppet said:


> great score and looks in pretty decent condition already. Looking forward to the rest of the rebuild. If you don't mind me asking, how much did you pay for it? I'm building up a mental picture of good prices for this size lathe for when I might be able to buy one in a year's time or so.



I believe I got a really nice deal on this @$500.  It included 3 and 4 jaw chucks, milling attachment and a fair collection of tooling, but I will need to learn how to grind my own cutters.   This was part of a package deal though and I got a garage that is a mess right now because of it.  So between getting the garage back in order, this rebuild and life's regular surprises I have plenty to keep me busy for a while.

Philip


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## mattthemuppet2 (Nov 29, 2013)

that's a great deal, especially with all that tooling, well done! Get to it when you can and keep up the enthusiasm, you'll get there eventually. I'm almost finished setting up my ancient mini lathe, over a year after a friend went west and gave it to me! Speaking of which, I should get out in the garage while the kids are quiet and do some more


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## Phonnold (Dec 16, 2013)

So, finally getting around to another update.  It has been bitter cold around here last couple weeks so working in the garage has been limited.  Had to move what I could downstairs and that is a small area I can work.  Limits me in what I can and how much I can do at a time, but I am moving along. 

So I tried to go with a 'Hammered Pewter" for the color but it isn't really what I thought it would be.  It is turning out to be more of just a silver as the texture that made it the hammered look doesn't always come out as you would expect.  Think it has to do with the size of the piece and the amount of paint you can put on.  So used to spray painting with steady even light coats to cover a piece.  This paint seems to need to go on slower and thicker to get the "Hammered" look.  But then it is more prone to running as the paint is thicker.  Ah well,  I am still happy with the look so it is going to stay and all the rest will get the same look.  


So far here is what I have been able to get done.  I feel I have done a lot, but haven't really touched the headstock hardly at all.  Tail stock has been cleaned, primed, painted and is ready to rebuild.  The countershaft spindle assembly that ties the motor to the headstock is apart and cleaned.  The main hanger that holds the pulleys has been primed and is waiting for its turn in the paint booth.  Need to find a source to replace the washers that are used around the bearings.  They seem to be a cloth ring of some sort and are shot.  Grease is just squeezing right out of the bearings.


Maybe it should be some, but I figure while it is apart to go ahead and replace these kinds of things so I don't have to be back in there anytime soon.

Most of the head stock covers have been pulled, cleaned and primed at least.  Have one of them painted, and it is a great example of how the "hammered" look doesn't really showing at all.




The carriage assembly is off and almost completely apart.  Only area that I am stuck is the carriage apron assembly.  I can't get the hand wheel off for some reason.  It looks like it just pulls off, but it isn't coming and I don't want to break anything.  From the diagrams that I have found it seems there is a woodruff key in there and I wonder if it has gotten messed up somehow.  Trying to get all the rest of the parts off of it before I really start messing with this stuck hand wheel.:thinking:



The compound rest assembly is totally apart and all primed at this point.  Wish I had a larger paint area and I could do all this at once.  Right now I have to do each piece one at a time and then let it site and dry some before I can touch it to put the next one in.  Here are some photos of the larger pieces for this assembly.







I see there is a set of photos on the camera still that I need to download.  At this point all of these are at least primer-ed.  Also if you look closely at the 4th photo of the swivel you can see some of that 'hammered" look appearing on this piece.  While all this painting has been going on I have been trying to get the saddle all cleaned and ready for its first coat of primer.  This piece has been the dirtiest so far.  The caked swarf and dried fluids was bad.  It is also the heaviest piece so far and that doesn't help either.  The center shaft area that the screw for the swivel rides in to move on was thick with chips and cutting oils.  At one point near the "front" it was just enough space for the screw, the rest was swarf and dried oils.  Took a scrapper to it so that I could at least get down to metal.  Going to take the degreaser to it one more time and hope that gets the last of it clean so that I can paint it finally.


Here is the closest I could come to a before photo.  Realizing later  that I am not getting the photos I should to document this and share it  with you all.


Here is how it sits right now.

At this point I am going to stop taking pieces off the lathe and apart until I have a few items built back up.  I have a lot of small parts, and while I have tried to keep them boxed and together I don't want to get them mixed up and not able to get something back together.  So next update should be some built pieces just sitting and waiting for the rest to get their time in the limelight.  )


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## schor (Dec 16, 2013)

Looking good. I also have problems with the bearing grease flying out. Let me know what you find is a solution.


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## Wierd Harold (Dec 17, 2013)

I just finished these yesterday (other then the adjusting bolt dimples) for my V42 rebuild .
I got the idea from another poster but can't find the thread to give credit. I always meant to do this on my older lathe because of the grease spreading problem.



HWF


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## schor (Dec 17, 2013)

So obviously simple. Thanks for that. I will build my own also.



Wierd Harold said:


> I just finished these yesterday (other then the adjusting bolt dimples) for my V42 rebuild .
> I got the idea from another poster but can't find the thread to give credit. I always meant to do this on my older lathe because of the grease spreading problem.
> View attachment 66151
> 
> ...


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## Phonnold (Dec 19, 2013)

That is a great idea.  So simple and also clean looking.  Wish I didn't have to get my lathe working to build those.


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## schor (Dec 19, 2013)

Harold, do you have a drawing with dimensions for the bearing holders and what bearings did you get?


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## Wierd Harold (Dec 19, 2013)

schor said:


> Harold, do you have a drawing with dimensions for the bearing holders and what bearings did you get?



This is the drawing I got on another thread. I did not use these dimensions exactly but just as an idea on how to get started. I changed things to match my bearings and just used "wing-it engineering" to get everything lined up and working. Also a copy of the receipt for the bearings I used. I haven't had this up and running yet but the countershaft sub assembly spins smooth as glass,





HWF


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## EOD1959 (Dec 19, 2013)

"They  seem to be a cloth ring of some sort and are shot.  Grease is just  squeezing right out of the bearings."
This past July I rebuilt one like yours and ran into the same thing with the felt rings, so I turned out a two piece cutting die and using a 100% felt cowboy hat punched out a bunch of the rings.
If you pm me an address and tell me how many you need I'll send them to you.

Dennis


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## schor (Dec 19, 2013)

Hmm, that could be an option. I'd really like to turn some new ones but I do have a ton of other projects on the go and this could hold me over. :think1:



EOD1959 said:


> "They  seem to be a cloth ring of some sort and are shot.  Grease is just  squeezing right out of the bearings."
> This past July I rebuilt one like yours and ran into the same thing with the felt rings, so I turned out a two piece cutting die and using a 100% felt cowboy hat punched out a bunch of the rings.
> If you pm me an address and tell me how many you need I'll send them to you.
> 
> Dennis


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## Phonnold (Dec 30, 2013)

So some items are going back together.


Also finally have main saddle cleaned, primed and painted.



Starting to rebuild this now.  A lot of small parts floating around now and I don't want to get anything lost so once this is done being rebuilt I will move onto the apron tear down.  Also going to pull the rest of the items off the main bed of the lathe and get it cleaned and repainted as well.  Feel like I am at a tipping point in that more is cleaned then dirty at this point.

@ Dennis (*EOD1959*),  PMing you about those felt ring replacements, think I could use a set here.

Philip


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## EOD1959 (Dec 30, 2013)

Sent you six rings.
Dennis

Check your jack-shaft pulley, I think it takes one too.


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## Phonnold (Feb 21, 2014)

Hey all,

So I have been working on this lathe, regardless of the lack of updates here.  I have been working the saddle rebuild and due to the small and many parts that are there I was taking it slow. Ran across some issues while doing this work.  If you look closely at the 1/2 nut on the first photo, before cleaning, you can see the built up dried oil and swarf at the edge of the nut, where it closes together.  When "closed" the nut wasn't really closed all the way and was really only grabbing just enough of the lead screw to work.  This has caused extra wear on the 1/2 nut threads and lead screw, to the point that it and the lead screw will need replaced I think.  It will be ok for cutting to size and auto feeding to get a cut done, but things like threading won't work anymore as the wear on this lead screw isn't linear so I couldn't get a thread that is the same the whole length of the screw.  The areas closer to the headstock have obviously gotten more wear then farther away.  I can see by eye this difference in the lead screw.  Tried to get some good photos of the 1/2 nut, but had some issues with this.








The last two photos of the lead screw show it off.  Should have gotten photos of it cleaned as well, but I think it still shows the condition, especially the last one.  The square threads are almost points near the left edge of the photo.  Anyone done a lead screw replacement and put in acme thread rod?  How  did that work with the gears that were there and didn't get replaced?

Other  items that have been done are the cleaning and painting of the main  body of the lathe.  This has allowed me to start rebuilding and makes me  feel like I am actually getting some work done.  Some before and after pictures of this.




But I also have a problem and I am stuck on an issue with the tail stock and hoping for some pointers.  The locking mechanism that locks the ram of the tail stock is binding when it is tightened and won't release the ram when it is loosened.  The following is how this was setup when I got the lathe.  The main screw that connects it all together is visually stretched.  Also the center ares of this screw the threads are shot.  Washers were added to the end so that different areas of the screw were used and there for only has but the barest of threads sticking out the top.



I replaced the screw with another one that had the same threading but had to grind the head down to get it to fit into the bottom piece of the locking barrel.  This gives a much better thread spacing into the handle.


But the problem is that the bottom barrel piece that does part of the locking seems to be twisting and binding in the channel it works in.  When I loosen it all this pieces stays bound up.  Everything else can come free and be removed.  This is the best photo I could get of it and you can sort of see that it is twisted against the ram body.


There aren't any burrs on the pieces or in the channel of the headstock.  Everything moves nice and easy when installed and only bids once you twist the handle to tighten it.  I don't feel like I am over tighten it, just enough to lock the ram from moving.  That really seems to be only about a quarter to half turn to get done, once the slack in the threads is taken out.  Any one else had this problem before or any ideas on how to deal with this?

Thanks in advance.

Philip


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## RandyM (Feb 21, 2014)

Looks like you are coming along very nicely. Keep up the good work. It is amazing at what you'll find when tearing a machine down and what all really needs fixing.

To answer your question, I will ask one. Have you lubed the parts? If you haven't maybe a simple squirt of oil will do wonders.


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## Wierd Harold (Feb 21, 2014)

It's hard to tell from the pictures but it looks like the angle on the bottom part is shallower then the top part and might be "wedging" tightly to the ram instead of just pressing against it. Maybe whoever did the washer trick filed the angle  ? If so maybe there is enough meat left to turn it 180 and grind the correct angle ?

HWF


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## schor (Feb 21, 2014)

RandyM said:


> Looks like you are coming along very nicely. Keep up the good work. It is amazing at what you'll find when tearing a machine down and what all really needs fixing.
> 
> To answer your question, I will ask one. Have you lubed the parts? If you haven't maybe a simple squirt of oil will do wonders.



I had my tailstock binding alot too, lubed it up and it works great now.


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## Phonnold (Feb 21, 2014)

Thanks for tips but it wasn't helped with oil on the pieces.  It is still binding up and won't pop free.  Top one is fine and comes "free" with no problems.  I will see if I can adjust the bottom angle to match the top and see if that helps any.  Wonder if there is other ways to get the ram locked?

On another note it seems I was mistaken and that the lead screw is already a acme thread.  Was looking through the manual and it seems to be a acme 8 threads per inch screw.  Totally missed that piece on other passes through the manual

Philip


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## wa5cab (Feb 22, 2014)

Phillip,

All Atlas lead screws are acme thread.

On the bottom tailstock ram lock piston, take a new condition fine flat file and run it across the bevel several times.  My quess is that there may be a low spot on the face so that along the single contact line, the line isn't straight, allowing the piston to twist.

Robert D.


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## Phonnold (Dec 16, 2014)

Hey all,

So this project isn't dead, or sadly competed just yet, and is still being worked on.  It is amazing how your free time just disappears when you have a kid.  Hope he is the best "shop accessory" every, but time will tell.  In the mean time some updated photos of the headstock area, and a question.






So I think I am at the point that if I had a motor I could power it on and get spinning things to spin and such.  I have manually driven the lathe and everything seems to be working as expected at slow speed and is adjusted.  I need to work on a lead screw and half nut replacement, but that won't keep me from using the lathe. But this leads me to my question.  The motor that is on this lathe isn't the factory default one, I think.  Last owner installed this motor with a custom drive controller circuit that allowed him to set the speed of the motor and thus the speed of the lathe, thus ignoring the quick change gear box.  This speed controller is very old and I would like to change it out because of this and that he told me not to trust it when I bought the lathe.  The selenium rectifiers that he used are getting old and leaking is the issue there I believe.​


So I have a motor that was being run on DC power via this custom  controller, but in looking at the name plate on the motor I think this  is really a AC motor.  My motor theory is low but I am aware that some  motors can run on both AC or DC.  My question is how can I confirm this  motor will be ok on AC without plugging it in and finding out the hard  way?  Here is the spec plate from the motor.


Model # is 5BC46AB349C
Now I know the first response is going to be "Google it".  I have tried and can't find any specs on this motor.  If you can, please direct me, if I could find specs I would be fine.

Philip


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## schor (Dec 16, 2014)

Looks like a standard 1/3hp AC 115V motor from the nameplate. Wire it up and try it. If it works, use it. Those lathes came standard with a 1/3hp motor. Check out some of my vids if you want to see ones I worked on and them running.

btw, controlling the motor speed does not negate use of the quick change gear box. The gearbox is for changing feed rates to the leadscrew.


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## wa5cab (Dec 17, 2014)

Steve,

NO NO NO!  The nameplate quite clearly says D-C MOTOR.  Plus it says that it is compound wound (COMP, which I won't bother to try to explain) which would also identify it as a DC motor.  Further, the nameplate says 115 VDC at 3 amps full load.  If you connected it directly to 120 VAC, you would quickly let all of the magic smoke out of it.  The small rectifiers are undoubtedly for the shunt field.  And the small transformer (although in the photo I can only see two wires) is probably for the field supply, although it could also be a filter choke.  

Philip

The controller is a simple one, with no electronics in it (it is not electronically regulated).  Looks like it consists of a motor starter relay, a Powerstat (that's a brand name, generic name is Variable Auto-transformer) for the main or armature variable supply, two rectifiers for the armature supply, and the much lighter fixed field supply.  You are correct in being concerned about the selenium rectifiers.  This wasn't known when they were first invented and commercialized but they turned out to have a 20 to 50 year typical shelf life.  Even if I couldn't see one dangling wire in the photo, I definitely would not try to use the controller as is.  Replacing the selenium's with silicon rectifiers is pretty trivial, except that you have to know what you are doing.  If you lived close to Houston, you could bring it over here and we could convert it (and shrink it by half).  But I wouldn't even attempt to try to tell you how to do it remotely.

On eBay tonight, I saw a few controllers for shunt wound DC motors but most are for either 230 VDC or for 1 HP or larger.  However I only spent a few minutes looking.  Most controllers are going to be for 90 VDC or 180 VDC permanent magnet motors.  Which will not have a field supply.  But a little looking should turn up one that will work.

However, 1/3 HP is a little light, even though that's what Atlas recommended in the 30's and 40's.  To get the lathe running quickest, I would buy a 1/2 HP single-phase capacitor start motor.  Later, you can if you like think about one of the other options.

Robert D.


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## schor (Dec 17, 2014)

Thanks for the correction and explanation wa5cab. Maybe I should just keep my fingers off the keyboard when I don't know something 100%.


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## wa5cab (Dec 17, 2014)

Steve,

Not necessarily.  But when acting on my answer could have unfortunate consequences if I'm wrong, I try to remember to put some weasel words in.  I've been wrong at least twice this year.  :whistle:And your comments on the QCGB were quite correct.  The distance that the carriage travels in one spindle revolution is independent of the spindle RPM.

Robert D.


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## Phonnold (Dec 18, 2014)

schor, I thought about the QCGB comment later and realized I was thinking on that wrong.

wa5cab, Thanks for the info, that kind of feedback is what I was looking for, even if it isn't what I wanted to hear.  I will poke around and see what I can find in regards to either a motor replacement or a controller replacement.  Was hoping to avoid that expense, but guess not.  When I think DC motor I think of a positive and negative connection and that is it.  This motor has much more than that, think there is 6 connections.  4 on studs and 2 wires that have been extended to the plug for the controller.  This is the best picture I have of the motor on me, can get better ones tonight if need be.



The controllers I am seeing just seem to be a two wire hook up, so not sure they would work.  Is there a "type" of controller I should be looking for?



Philip


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## wa5cab (Dec 20, 2014)

Philip,

There are four basic types of DC motors - Series, Shunt, Compound, Permanent Magnet.  The Series type is AC/DC, is sometimes called Universal, and is seldom found in sizes above about 1/10 HP.  Your motor is compound wound, and is the only one of the four that should have 6 wires.  The permanent magnet type only has two wires.  The series and shunt will have two if they are not intended to be reversible (the four wires are tied together internally) or four if they are reversible.  

The two-wire controllers that you have found are most likely all for  permanent magnet motors.  They will run the other three types but the  Reverse switch on them will not reverse the motor.  The one that you would want should say for compound wound motors.  If all that you can find is one for shunt wound motors, this will work but you will have to outboard the reversing switch.

Two wires will go to the armature.  Two will go to the series field.  And two will go to the shunt field.  I can't really think of a logical reason for yours to have 4 studs and 2 loose wires instead of 6 studs.  If the motor is going to be reversible, you have to flip both field windings.  Below are stylized wiring diagrams and schematics of the first three types.

If you cannot ID which of the three windings the studs and wires go to, using an ohmmeter, the series winding and the armature will have very low resistance.  The shunt winding will probably be several thousand ohms.  To differentiate between series and armature, pull one brush to ID the armature.

Note that to reverse the compound wound motor, you either reverse both windings or the armature.  Reversing the battery will not reverse the motor.

Also, the drawing below, which originally came out of a WD training publication, had an error on the shunt and compound wiring diagrams.  I corrected the error by moving the battery connection to the right end of the shunt field winding from the positive to the negative battery terminal.

Robert D.


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