Eliminating Backlash, Part 2: Refinements If you're looking over this page, I'll assume you have a machine already converted that has the "good" parts (like ballscrews), you've gotten rid of most of your backlash (let's say you're down to 0.005" or less), but you still have too much backlash. If instead you either, wonder why you should eliminate backlash (or how much can your stand), you want to build a CNC machine from scratch, or you are converting a manual machine that has measurable backlash, try Part 1.
I Installed , And Still Have Backlash. What Should I Do? First, make sure you do in fact have the Good Parts on your machine and that they are installed in the most advantageous way. If you have any doubt, you might just quickly peruse Part 1. Okay, so you have the good parts and still have backlash. How to go about diagnosing? Simply put, there are just a few areas that can be sources of the backlash on a given axis:
Leadscrew & Nut
Leadscrew and/or Nut Mounting
Motor Drive Mechanism
Slideways and or Gibs
Machine Flexure and Rigidity
Let's look at each one, describe how backlash can develop there, and discuss what you might do to
All material © 2001-2009, Robert W. Warfield.