Paul,
I have converted a round column (RF 31), and can highly recommend AGAINST retaining the original lead screws! The reason I say this is that is what I did and in a matter of just a few weeks running it under power like that, simply wore out the screws (well actually the brass nuts). When I got my ballscrews in, I took the lead screw and nut (X axis) and could actually "walk" the nut down the screw without turning anything
The measured backlash towards the end or the running of the original leadscrews got up to 0.250" (no thats not a typo) and was a combination of the wear in the screw and the fact that I could not tighten the attachment bolts tight enough to keep the nut (again the X axis) from moving. When I made the new holder for the ballnut, I pinned it to the saddle. Haven't had a problem with that in a couple of years now
You can see how I did several things on my web site which is noted in the tag line.
Also, I have a drawing file that I used to make the parts. It is more like a series of sketches but has a lot of information in it. Let me know if you would like a copy.
Also to answer your question about backlash compensation, I advise against relying on that. If you get into a situation where you are doing any climb milling, you run the very real risk of tearing something up! For example, doing any G02/03 cutting can easily put you into that situation. Also, your circles will NOT be round if you have any appreciable backlash (don't ask how I know
Bubba
10-26-2006, 10:21 AM
Linear Mode
