Yup, at 10 lbf. But based on how it “felt” and experience/intuition (which may have been misguided) I didn’t consider drive belt stretch. Unfortunately Gates seemingly doesn’t make modulus of elasticity data for their GT2 (or newer GT3) belts readily available. But, its easy enough to measure to enable simple belt comparisons. Just clamp some nearly fully open calipers to the belt and measure the length increase as a function of force (with weights?). What size Shapeoko do you have?