I had made a new split cross slide nut like that for "fullautomike" when he was rebuilding his Harrison M300 lathe, along with a mating screw. On my own Victor 1640, I had simply bought a new screw & nut set from the manufacturer. Both work in a similar fashion, though no pins to slide on. The one in my lathe has held position perfectly for years, zero backlash between the 5/8-5 ACME thread and the nuts. I don't know how Mike's is working because he seems to be an "unregistered" member here now.
The only problem I have with mine that I cannot seem to fix is the pair of nuts on the end of the screw which keep unscrewing themselves and giving me lots of backlash. They are fine pitch bearing nut style with a tabbed washer between them. The washer is definitely keeping the two nuts tight to each other, but they back off together. Any ideas on how I might fix it? I'm thinking my only alternative is to mash the threads between the outer nut and the end of the screw using a center punch. I'm open to any suggestions.
Here's what the nuts I'm referring to look like.
![[Image: X_slide_rear.jpg]](http://img.photobucket.com/albums/v466/kenm10759/Dads%20shop/X_slide_rear.jpg)
![[Image: Z_scale_low_rear.jpg]](http://img.photobucket.com/albums/v466/kenm10759/Dads%20shop/Z_scale_low_rear.jpg)
The only problem I have with mine that I cannot seem to fix is the pair of nuts on the end of the screw which keep unscrewing themselves and giving me lots of backlash. They are fine pitch bearing nut style with a tabbed washer between them. The washer is definitely keeping the two nuts tight to each other, but they back off together. Any ideas on how I might fix it? I'm thinking my only alternative is to mash the threads between the outer nut and the end of the screw using a center punch. I'm open to any suggestions.
Here's what the nuts I'm referring to look like.