Shopsmith Forums

After cleaning up my new sixties vintage ss, I started playing with it, mostly low speed sanding and lathe work. When I did some routing at high speed, after about a twenty minutes a loud buzzing noise developed.
After shutting it down, spinning it manually, the rotation was jerky, having a tight spot about every 20 degrees of rotation.
The machine has been lightly used, bearings are tight. I tore it down and everything looks good. The motor is quiet and smooth, the idler shaft spins nicely (at low speed), the same with the main shaft. Upon reassembly, the jerkiness was gone.
Listening to the noise, it seems loudest through the speed control opening.
I have oiled everything, with no effect.
The belts are original.
Any ideas would be appreciated. The noise starts at mid speed.

nh3
Tough call with the info given. When it happens again try to remove the quill quickly and with the sanding disc on the auxiliary shafts at the left end of the headstock and see if the stick rotation is still there. This eliminates the quill bearings.
Next step is to remove the belt from the motor and try again. If the stickiness is still there I would suspect the drive shaft bearings. Those are the 6205 bearings that are visible at the ends of the casting.
Divide and conquer.
Bill V

Is the loop attached correctly to the porkchop?

Do the belts have a 'set'?

Define 'tore it down'.

Bearing(s) may have gotten hot.

wa2crk wrote:nh3
Tough call with the info given. When it happens again try to remove the quill quickly and with the sanding disc on the auxiliary shafts at the left end of the headstock and see if the stick rotation is still there. This eliminates the quill bearings.
Next step is to remove the belt from the motor and try again. If the stickiness is still there I would suspect the drive shaft bearings. Those are the 6205 bearings that are visible at the ends of the casting.
Divide and conquer.
Bill V

I have removed the belts, inspected, and reassembled the machine. The motion is now smooth, I mentioned it because it suggests something had moved. My main concern is the noise.