Cheap and dirty lathe conversion.. (Old Nebel lathe)

[Bob La Londe]

I have a brand new one... in a box somewhere.

[skunkworks]

Putting the ball screw in the cross slide (x axis) we are mounting the stepper on the back side of the lathe. So - we needed to put a hole in the back side of the saddle for the ball screw to pass though. Found an old shaft (threaded on one end - no clue what it was from)

turned down the end so it would pass through the existing brass nut and used it to drill and bore the back side of the saddle...

[skunkworks]

used the same shaft and made a boring bar. This should allow us to center the ball screw, bearings and motor mount is perfectly allinged..

[skunkworks]

Dad shaped the ball nut housing to fit into the slot. I bored and drilled/tapped the holes to mount the nut and the bolt to mount the housing. The ball nut needs a bit of flange removal - you can see it overhanging the nut housing.

[skunkworks]

getting closer... Dad ground the ball screw nut to size. The nut and housing seem to work great under the cross slide...

[RB211]

I have a Drewtronics touch probe on my Taig, love it.

[skunkworks]

Just have to make the motor mount... The cross slide has about 17 inches of travel...

[RB211]

When mounting the ballscrew, at least the ones I have, the threaded section of course takes a nut, but there is no register against the ball threads. So what is the proper method to remove lash? Angular contact bearings preloaded with a nut on the threaded side, what about the other side?

[skunkworks]

RB - do you have a picture? I am not understanding what you mean. Mine had a machine section between the ball screw and the threaded section. I made a bearing block that has a section that keeps angular contact bearings apart. The nut pre-loads the bearings. (going to use jam nuts.) the opposite end - we just have a bearing to keep it from flopping around..

[skunkworks]

Sorry - forgot to quote you ^

RB - do you have a picture? I am not understanding what you mean. Mine had a machine section between the ball screw and the threaded section. I made a bearing block that has a section that keeps angular contact bearings apart. The nut pre-loads the bearings. (going to use jam nuts.) the opposite end - we just have a bearing to keep it from flopping around..

[RB211]

Sorry - forgot to quote you ^

That makes perfect sense, except there is no hard shoulder opposite the threads to preload the bearings unless one bearing is up against the ball threads.

[skunkworks]

if it is a different diameter? isn't it a hard stop?

[RB211]

if it is a different diameter? isn't it a hard stop?

I suppose it's good enough, I just don't like it!

[skunkworks]

Lol.. it will probably work just fine..

[skunkworks]

almost ready to test the X axis...