DocsMachine
Well-known member
- Joined
- Sep 16, 2006
- Messages
- 1,857
I'm in the middle of rebuilding an older Wellsaw horizontal bandsaw, and got around to checking over the motor. It's an older 3-phase unit with an odd post mount, and ran just fine other than a little worn bearing whirr and a wobbly pulley.
The bearings are an easy fix, of course, but in looking at the pulley, I found out it's okay, it's the shaft of the motor that's the problem. It looks like somebody hit it with a ******* file while it was turning, probably to try and smooth down a burr after a key sheared or something.
It's supposed to be nominally a 3/4" shaft, but spots measured as low as .732".
So I made an aluminum collar to protect the bearing surface, and piled on some MIG weld to try and put some of that metal back.
Then, with a steady rest in the lathe, riding on the clean bearing surface, I was able to single-point the 60-degree center in the end of the shaft to make sure it ran perfectly concentric with the rest of the rotor.
After that, the rest was a simple turning exercise.
Apart from the interrupted cut at the beginning, of course.
And, with a little care and patience, the fix came out perfect and on spec.
I still need to cut the keyway, but after that, it just needs a fresh set of bearings and the motor's good for another couple decades of use.
Doc.
The bearings are an easy fix, of course, but in looking at the pulley, I found out it's okay, it's the shaft of the motor that's the problem. It looks like somebody hit it with a ******* file while it was turning, probably to try and smooth down a burr after a key sheared or something.
It's supposed to be nominally a 3/4" shaft, but spots measured as low as .732".
So I made an aluminum collar to protect the bearing surface, and piled on some MIG weld to try and put some of that metal back.
Then, with a steady rest in the lathe, riding on the clean bearing surface, I was able to single-point the 60-degree center in the end of the shaft to make sure it ran perfectly concentric with the rest of the rotor.
After that, the rest was a simple turning exercise.
Apart from the interrupted cut at the beginning, of course.
And, with a little care and patience, the fix came out perfect and on spec.
I still need to cut the keyway, but after that, it just needs a fresh set of bearings and the motor's good for another couple decades of use.
Doc.
