Quote Originally Posted by 109jb View Post
80 pounds of torque? If you mean 80 inch pounds that would equate to 1280 oz-in and about 2300 pounds of axial screw force for a 5mm lead ball screw. I would not call it backlash with the gibs locked down. Backlash should be measured with properly adjusted gibs using a dial indicator to determine the backlash.
To clarify we have already adjusted the gibs properly with a dial indicator. We are trying to identify other causes of backlash at this point. lubrication is also ruled out.