[HomeCNC]

If you are gaining steps you can eliminate the IPM speed as a factor. If you push the machine to fast you will loose steps never gain them.

Are you sure that you have your math correct for calculating how many steps it takes to move 1 inch? Have you placed a dial indicator on your machine and told the controller to move 1 inch and looked at the indicator to see if you did move 1 inch? Do this on all three axies.