My roommate’s blender (Oster 6844) has stripped the threads that connected the motor shaft to the coupler. Buying a new coupler is cheap and possible, but the threads have been stripped off of both the coupler and the motor shaft.
Any google search results about stripped threads/couplers are actually referring to the square stud, so I don’t know if it’s possible to fix this. Any ideas? There’s a fair bit of play since both sets of threads are pretty much gone, so I don’t have a lot of confidence in, say, using epoxy to fasten it back on.
The stripped motor shaft is 4.5mm diameter at its thinnest and 5mm where the threads still sort of exist. The shoulder (still part of the shaft) is 8mm dia, but has very little overlap with the coupler. I’m not sure if there’s enough material there to be drilling a hole through it. Also, the coupler has a large plastic part that I think is meant to reduce shock to the motor, and I suspect it might not like to be drilled through.
Yeah, I’ve thought about rethreading the shaft, but I’m afraid it might be too thin to thread. I’m assuming there’s a fair bit of strain on this area, given that the original threads wore off.
I eventually decided to glue the coupler back onto the blender with JB Weld. Despite my best efforts, it wasn’t centered enough and the eccentric motion created too much resistance. But after an hour or so of filing (with a diamond file, because the coupler is hardened) the eccentric motion was reduced enough that it is working again. So that’s good.
