PM-1440GS Working on Feed Gearbox

[DavidE]

Anyone know the easiest way to get into the feed gearbox. Can I just remove the front plate or do I need to take off the whole gearbox to work on it.
I have to figure out why the leadscrew coupling is moving in and out about .003. It causes problems threading close tolerance threads. My lathe was bought in 2016 it didn't have thrust bearings on the right end of the leadscrew so I added them. It helped a little but did not solve the problem. I think something in the gearbox was meant to control the thrust on the leadscrew and it may be causing the problem. I didn't want to pull off the front of the gearbox to look inside and get everything out of place. Thanks for any advice, David

 

[matthewsx]

I think there’s another recent thread on here that addresses this problem.

Conclusion there is that there is almost always some play and the solution lies in letting the machine take up the play before starting the thread.

I’m no expert on this but it may be worth doing some searching before taking your machine apart.

John

 

[DavidE]

Thanks for the advice. I did try everything to take out any play first, I thought that would be the problem but it wasn't. Then I checked the leadscrew. Something in the gearbox is forcing the leadscrew left and right .002-.003

 

[matthewsx]

Here's the thread I was talking about.

Question about cleaning up freeplay / backlash in Enco 12x36 lathe leadscrew

So, I have noticed that my leadscrew has some backlash / freeplay in it. With an indicator on the ways, up against the carriage, with halfnuts engaged, moving the carriage handwheel will read about 20thou of free play in the leadscrew. I have to assume this is not helping my threads at all...

www.hobby-machinist.com

 

[DavidE]

Here's the thread I was talking about.

Question about cleaning up freeplay / backlash in Enco 12x36 lathe leadscrew

So, I have noticed that my leadscrew has some backlash / freeplay in it. With an indicator on the ways, up against the carriage, with halfnuts engaged, moving the carriage handwheel will read about 20thou of free play in the leadscrew. I have to assume this is not helping my threads at all...

www.hobby-machinist.com

Here's the thread I was talking about.

Question about cleaning up freeplay / backlash in Enco 12x36 lathe leadscrew

So, I have noticed that my leadscrew has some backlash / freeplay in it. With an indicator on the ways, up against the carriage, with halfnuts engaged, moving the carriage handwheel will read about 20thou of free play in the leadscrew. I have to assume this is not helping my threads at all...

www.hobby-machinist.com

Thanks for the thread. David

 

[Hozzie]

So, you can definitely get into the feed gearbox by just removing the front plate and then removing the bolts holding on the cast front plate. Make sure you have a way to create a gasket when you put it back on.

I am upgrading to the 1440GT due to some issues I have also had with the GS. I had/have issues where the feed settings would just kick out and ruin an entire thread, so if you aren't having that issue, consider yourself ahead of the game. I wouldn't open it if I absolutely didn't have to. I have had to have mine apart probably 5 times.

 

[DavidE]

So, you can definitely get into the feed gearbox by just removing the front plate and then removing the bolts holding on the cast front plate. Make sure you have a way to create a gasket when you put it back on.

I am upgrading to the 1440GT due to some issues I have also had with the GS. I had/have issues where the feed settings would just kick out and ruin an entire thread, so if you aren't having that issue, consider yourself ahead of the game. I wouldn't open it if I absolutely didn't have to. I have had to have mine apart probably 5 times.

I have plenty of gasket paper. Just didn't want to pull off the front cover and get something out of place and not get it back where it goes. I see in the parts drawing it has access covers on top. I wasn't sure if I would need to pull them off also.
Thanks for the information.