David,
Usually if you miss a step you know it/ can hear it and the result can vary from a minor position loss to the table just going off with a mind of it's owne.
I will echo what has already been posted.
I don't know what size steppers you are using, but as a rough guide :
- See where the axis will just start skippping on a rapid move, and reduce the velocity to 50%. ( 90 ipm goes to 45 ipm)
- Now do rapid moves for a short distance of say .2" start to finish and see if you lose position, if so reduce the acceleration ( at 45 ipm try accel of 5 )
- If all is well at 40 ipm, then just cut some material at varing depths in increments of say .050" in Al and see what happens.
BTW, IPM (Feed Rate) = # end mill flutes x chip load x rpm
ie: 26=4 x 0.001 x 6500 and chip load becomes important with smaller HP equipment
RICH