So far it has not been subjected to heavy load but I expect that the (almost) 2 to 1 ratio not subject the splines to an over stressed condition. I’ve made several 22t gears in different materials (TPUd75, PCTG, PLA) with different spline counts, Each is a tight push fit and I’ve used one of the two long screws supplied to secure to the drive shaft. Some spline counts fit like a glove with others require a fair old push on the gear to get it seated. I’ve attached the parts but be aware I’ve not load tested yet. I have only lifted the boom off the floor so far. Although the motor handled it more effortlessly than the previous ratio.
Yep, it just failed under 1.2kg. Further investigation required.
Not slipping on splines but jumping gear teeth. Either the teeth a too small or the clearance is too big. Or it could be TPU is too compliant. Will swap it for the PCTG gear and see what happens.