Hi Ant,

To adjust the jibs It's best to take the motors off so you can turn the ball screws by hand you can then FEEL for any binding so get them as snug as you can but no binding. The best place to do this is at the extremes of travel as this will be the tightest area.

To test for backlash you need to have a DTI in a chuck or collet

You gently come up to a smooth face zero the DTI and zero the DRO

YOU CONTINUE TO WIND THE DTI ONTO THE FACE A SMALL AMOUNT 0.2mm say

Then you gently back off the face until the DTI reads zero

Your Backlash will be what the DRO reads

Wind the Z down about 75mm put a dowel in a collet chuck have the dowel sticking out 30mm put the DTI on the dowel at It's end push and pull on the collet chuck to measure play in the quill/housing.

Phil