Clever antibacklash nuts for your CNC machine

Those of you who have experience with CNC understand the importance of low backlash leadscrew assemblies. Without them, there is slop between the rotary motion of the axis drive motors and the linear motion of the machine. This keeps the controller from knowing exactly where the slide is, leading to reduced accuracy among other issues.

A proper CNC machine uses preloaded ball screws to eliminate backlash, but those are out of the price range of many homebrew CNC projects. [Evan] has come up with a great way to make precision lead screw nuts for cheap, with a small collection of simple tools.

The nuts are made by heating the threaded rod and clamping two pieces of acetal plastic around it. The plastic flows into the threads, creating a perfect fit with very little clearance. All that’s left is to fab up a way to mount it to your machine’s axis. [Evan] uses a lathe to make his nut fit in a round mount, but that’s not entirely necessary. With a little creativity, I’m sure you can find a way to apply this great idea to your machines. They’d definitely be helpful to [Joel] as he works on his CNC conversion.