Ball screw backlash

[Aiph5u (Aiph5u (not affiliated with Onefinity))]

I think a good test for rigidity is this one .

But ball screw backlash is something different. I don’t know why you want to replace the ball screws.

I would adjust their play:

@OnefinityCNC

7) End Nut Adjustment

Ensure the nut on the rail end is properly tight. Too tight and the ball screw will not move, too loose, and the ball screw will not spin when the motor spins. There is a washer behind the nut. Proper tightness is when the washer behind the nut can just barely spin freely. Adjustments should be made in ¼ turns.

Foot Pound Torque Setting is around 4 lbf⋅ft ≈ 5.4 Nm

For the rest, I would agree to Tom