as audiobugged stated you may have to raise or lower motor to line up with groove on platter,also rather than turning on motor,turn platter slowly by hand,you can also put your hand on top of the belt lightly next to pulley to keep it from jumping off untill it moves to the correct platter groove ,by turning platter slowly by hand you will be able to see why the belts coming off,hope this helps,,
scout drive belt keeps slipping off
I have the VPI Scout and I can't keep the belt from slipping off the platter. The second I turn on the motor it slips off. I've tried talc and that doesn't seem to help much. What's the secret here?