Hi, I want to thank everyone who has given me advice on this forum. It looks like I have solved my problem. This morning I swapped the usb cable that goes from my breakout board to a 5v phone charger. Instead I placed the usb cable into the usb port of the laptop I am using. Then I altered the stepping settings from 1/4 to 1/16 on the z axis driver and kept the other 3 drivers at 1/4 stepping. Altered the ipm to suit the new stepping on z axis and ran a job and it was perfect no lost steps, no bit raising or lowering below the work piece. So to make sure I ran off 4 different projects this afternoon all perfect. Hooray.

So a big thankyou to everyone who responded to my post.

Cheers Neil