My Dyson vac cleaner head brushes stopped spinning because the impeller cracked in half. Couldn't find a spare part anywhere, and didn't want to spend $150 on a new one. So drew it, printed it, fitted it and all good again. Dare say works better than the original ;)
printed 0.2 and fine on UP mini, but I think quite forgiving. Position of shaft can be adjusted slightly (may need to be), but this is easy as is a press fit. Let me know if you have had this problem and I will "talk" you through it..