I played around with the ratio tonight and set it to 5.35 which brings it almost correct after some trial and error adjustment. I did this by measuring distance travelled etc. There is no screws on this axis just belts, i've set the drives at 16 microsteps (3200). definitely confident that it is not loosing steps as it will always return to point zero every time. Still managed to cut a few sample pieces which turned out rather nice in comparison to my old machine. I will spend some more time tomorrow playing with the ratio. I will rig up the DTI rather than judge by ruler which is what i did tonight. the belt is 5mm pitch, if you look at the pics it shows the end of the X axis. It runs with belt both sides powered by the single stepper (4amp bi parallel). Using PM542's on a Uniport V2 bob, kept to 5mm pitch screws on Y and Z. The Y has 24T pulleys 1:1 config and these axis are absolutely spot on