I just purchased 4 more belts. There was one belt in the cabinet so now there are 5 spare belts. The last time I used the Tormach I notices some slipping. I tightened the belt. Make sure you have proper tension on the belt. There should be 1/8" to 1/4" deflection of the belt between the pulleys with firm finger pressure. Any more flex than that will allow the belt to slip under load.