Thanks Jim. I tried a few different feeler gauge thicknesses and found out that once the backlash/clearance is taken up it doesn't take much more to lock up the ball screw. So in my situation it looks like .002 - .0025" should do it.
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Chasing Backlash
- Thread starter TomS
- Start date
Thanks Jim. I tried a few different feeler gauge thicknesses and found out that once the backlash/clearance is taken up it doesn't take much more to lock up the ball screw. So in my situation it looks like .002 - .0025" should do it.
Took a month for the shims to arrive but it looks like shimming the two nuts solved the backlash problem, I hope. I tried a .0025" shim between the nuts but it locked up the ballscrew. Put in a .002" shim and you could feel a slight drag when turning the screw by hand. I installed the nuts and screws and adjusted the gibs. The X axis gib was easy but the Y was problematic. The adjusting screw that moves the gib inward was twisting the gib. I was getting line contact on the top and had a large gap on the bottom. I've had problems with these adjusters before so I made a plate that uses a set screw to push the gib in. Works great!
Here's a picture -
For the backlash check I clamped a piece of 1/4" thick aluminum in the vise and pocketed a 1-1/2" diameter hole. The hole was round within .0005". Tried the pocketing routine three more times with the same results. Maybe, just maybe, my backlash problem is solved. Only time will tell.
Here's a picture -
For the backlash check I clamped a piece of 1/4" thick aluminum in the vise and pocketed a 1-1/2" diameter hole. The hole was round within .0005". Tried the pocketing routine three more times with the same results. Maybe, just maybe, my backlash problem is solved. Only time will tell.