My record 220 has a drill bank that is driven up and down by a stepper motor gear driven into a cogged metal lined belt.
The problem I am having is as the drill head does a line boring operation or any multiple drilling ops the depth that the drill go gets to be less and less. They may start out drilling to a depth of 3/4" but by the time it is done it may barely be touching the workpiece. If I reset the drill head to the home position it will start out ok but by the time it is done same outcome. I have replaced the stepper motor and the drive belt that it uses. So these 2 items should be back to new condition. If I do not reset the head to home position after each run the drills go deeper with each succeededing run. After a few the drills wont evan clear the workpiece. Have called scmi with the problem with no good help. They have a rack system to replace the belt. At one time mine worked fine so if I have the belt replaced and the motor replaced this should eliminate the mechanical end of it. I hace no exp with the stepper motor drives. I sure could use some help on this or a good tech to talk to about it. Thanks to all who respond. Sorry so long winded.
Jay White
White Custom Millworks
Belle Plaine Ks