# Just purchased an Atlas 48TV lathe



## dbq49 (May 11, 2014)

Having just cleaned up the lathe and gave it a new coat of paint.  I am now trying to find the tools and parts I need to make it it work.  I have noticed some wear on the 3/4" lead screw about 4" long about 4" from the head stock. Has anyone tried to cut a new lead screw that has an 8 pitch square thread?  Also what is the purpose of the 3/16 keyway along the length of the lead screw?  I only foulnd a 54" lead screw on Ebay but it might not be in any better shape.  Would a machine shop make one?
Thoughts please.


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## pdentrem (May 11, 2014)

The wear near the headstock is typical of all lathes. The thread is NOT square thread, it is Acme. Some users have cut the section to the left where the threads start and flip the threaded part end for end and reattach the cutoff section via a sleeve that is pinned to the two parts. One of the pins being Brass or Aluminium. This gives you a shear pin to help protect the lathe from severe damage.
As for the groove along the leadscrew, it is part of the drive system for powercross feed at the saddle. 
Leadscrews are not cheap, the error per foot has to be as minimal as possible. Most important if making threaded shafts.
Pierre


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## dbq49 (May 12, 2014)

Thanks Pierre for the response.  Can you buy acme ready rod and cut in a key slot to make a lead srew?  I put on a linked belt but I am concerned that I would like to convert it from a vertilce countershaft (9-20X) to a horizontal countershaft assembly (10-20X).  I see holes on the bottom plate of the horizonal assembley but on the parts list I don't see how it attaches to the headstock or ways.  Dbq49er


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## pdentrem (May 12, 2014)

dbq49 said:


> Thanks Pierre for the response.  Can you buy acme ready rod and cut in a key slot to make a lead srew?



Yes. One of our members just did so not that long ago. Have to do a search. Here you go. There is a couple topics, so you have to follow along. 
http://www.hobby-machinist.com/showthread.php?t=18061&p=179681#post179681

Why convert from vertical to horizontal? No advantage that I can see in doing so.
Pierre


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## Dranreb (May 13, 2014)

Having started with a quite worn Atlas lathe myself, my advice would be to ignore any thoughts of changing anything at all before you get the feel of setting up and using the lathe.

I don't know what experience you have but I doubt the lead screw wear will have much effect on most things a you are likely to try at first. Much better to get on with making chips, but keep an eye out for parts and maybe another better lathe will come along that is cheaper than fixing yours, this worked for me.

Have fun..

Bernard


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## dbq49 (May 13, 2014)

Bernard
I am a retired 35year high school technology teacher.  I have taught beginning metals on 15 10" south bend lathes.  Maintenance is how you keep machines running.  I understand the Atlas is a lighter machine but it turns metal just fine, speed and time is not a concern.  What are you using instead of Keystone 122 gear lube.  I tried chain oil but it seems to fluid and flew off easily.   I did not find an 8 threads per inch ready rod and then thought about the kind of steel in the ready rod.  Does your Atlas have a vertical or horizontal assembly?  The vertical over center roll bar seems more likely to vibrate off rather than the lock system on the horizontal assembly.  Just lots of learning on this style of machine.
Dbq49


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## pdentrem (May 13, 2014)

I was using Mobiltac Open Gear Lube. Mine came in a spray. Very old stock. Here is a link to current info. Others do sell this stuff, likely repackaged Mobil.
Pierre

http://www.exxonmobil.com/MarineLub...hinery_open-gear-systems_mobiltac-375-nc.aspx


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## iron man (May 13, 2014)

The store bought Acme rod you need is here you can buy it in about any grade the least expensive one is just as good as the stock Atlas one.

http://www.roton.com/mating_components.aspx?family=7059433


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## Dranreb (May 13, 2014)

dbq49 said:


> Bernard
> I am a retired 35year high school technology teacher.  I have taught beginning metals on 15 10" south bend lathes.  Maintenance is how you keep machines running.  I understand the Atlas is a lighter machine but it turns metal just fine, speed and time is not a concern.  What are you using instead of Keystone 122 gear lube.  I tried chain oil but it seems to fluid and flew off easily.   I did not find an 8 threads per inch ready rod and then thought about the kind of steel in the ready rod.  Does your Atlas have a vertical or horizontal assembly?  The vertical over center roll bar seems more likely to vibrate off rather than the lock system on the horizontal assembly.  Just lots of learning on this style of machine.
> Dbq49



I have tried most oil lubes for the gears, if it doesn't fly off it all just drips off later...never used grease because of chips, today I used 140 'vintage tractor gear oil', ran nice and quiet too. I mostly over lube everything and my chip tray will never rust. 
	

		
			
		

		
	




Mine is a vertical counter shaft, it flexes about as the pulleys are a bit wobbly as most seem to be, but the over center bar has never unlocked itself, it was a bit worn so I welded and filed it back to shape.

I'm happy with mine, it is a little bit lighter than I would like as I get more adventurous but I won't bother getting a heavier type. Today I turned down the worn bull gear shaft for my shaper between centers, I did a few test cuts on another piece of steel to check the run-out, tool shape and speeds but got a ripple in the surface. After checking and re-checking everything I found it was the automotive belt I was using on the motor to counter shaft pulleys, which had that indented inner side like they have nowadays. I had previously tightened as it had worn and the indents being lower in the groove affected the finish.

I also added another compound gear to get a slower feed.

After all that, when I'd done the job I took it around to a retired machinist mate for checking and measuring properly (don't trust mine) he reckoned the finish is a better than new would have been and he couldn't find more that half a thou variation anywhere, this is the best work I've done on my Atlas and I'm a bit chuffed to say the least....
	

		
			
		

		
	



You're right they turn metal just fine, tomorrow the entirely different challenge of making the bronze bushes to fit the shaft...
	

		
			
		

		
	




Bernard


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## dbq49 (May 14, 2014)

Thanks Iron man for the link for the acme thread rod.  I went to site but did not see a choice of materials but I could call for  more info.  I also looked at the other links to see how others used a mill to cut in a keyway.  Good Info.!!!!
Bernard, I installed two linked belts on the lathe and set the handle back to put tension on the belts.  I found the handle hit the motor case so I bent the handle so it would allow it to stay in place.  I will see if it rattles loose during use.  As you stated I could weld more on it I needed.  The belts on the lathe when I got it were BAD so I thought I would try the linked style.  Sure was nice not to have to break down the head to get it on.  I just love getting this good info over the net.  You just can't get this much help locally.  Everyone can help and we all can learn something if only we share.  I still need to buy tooling but it will come
Dbq49


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