jj3inc,
Hey, you seem to know your basics on gears! Getting through such good info in so few words indicate you know a lot about this. I have a problem you may be able to help with:
My mill is now 2/3 converted to CNC. The Z-axis is still manual. There is no way I can figure out to use ball screws without introducing unwanted flex, so I was thinking whether I can improve on the existing rack & pinion. The rack is milled in as part of the quill, so no way I can change that. What I thought about is to cut a new and oversize pinion. I know this should ideally be done for both the rack and the pinion and with a modified tooth form, but as I said: not possible here. I now have around 1/4mm backlash (in rack movement), and would ideally like to have a slight preload instead, but better than 0.1mm will be OK. It's Metric Mod 1.0, 17 tooth pinion. Should I forget to even try?
If I try, should I use the #3 cutter (17-20) to cut the pinion, or will the #2 cutter be a better match to the modified form?
Or should I wait until I have the hob set up. It's not really high on my priority list.
Thanks for any input you have on this, it is quit a bit beyond my knowledge on gears.  |