So the other day the press on ring on the stepper cog popped resulting in the belt being cut. So in looking at the GT2, I noticed in the spec it states the working tension is 6.25 lb. this should be the tension on the belts on the Xcarve? I would assume so since the teeth spacing, angle of the teeth and the radius are most likely measured under load. This could explain why my machine started cutting closer to machine tolerances stated by Inventables after I increased the belt tension up to 5 lbs.
Specs from Inventables web site.
6.35 mm width
Color is black.
Material is Neoprene (for quiet operation)
Reinforcing Cords are Fiberglass (belting can be easily cut with regular scissors)
124 lb / 56kg Breaking Strength
6.25 lb / 2.8kg Working Tension