Shopsmith Forums

I’ve installed my Power Pro and everything seemed to go ok. However, the eccentric keeps sliding back in the headstock casting when using my jointer. I’ve been able to move it back into position by loosening the bolt and nut in the headstock casting and then retighten everything. I did the speed test and everything runs smooth with no noise, but every time I attach and run the jointer the eccentric moves. This also causes the upper belt to jump a grove when the eccentric is pushed back. Very frustrating.

Quit applying pressure to the coupler when attaching the jointer.

Let there be some clearance(horizontal slop in the coupler).

Linus wrote: ↑Tue Jan 07, 2025 4:46 pm I’ve installed my Power Pro and everything seemed to go ok. However, the eccentric keeps sliding back in the headstock casting when using my jointer. I’ve been able to move it back into position by loosening the bolt and nut in the headstock casting and then retighten everything. I did the speed test and everything runs smooth with no noise, but every time I attach and run the jointer the eccentric moves. This also causes the upper belt to jump a grove when the eccentric is pushed back. Very frustrating.

If you keep the jointer out of the setup..does everything work right?

When I first put my Gen 1 PowerPro together I had some trouble with Idler Shaft inward migration even when it wasn't driving a load. The primary issue was that the lower belt wasn't running true, or perpendicular to the Idler and Motor Shafts. This, combined with normal vibration, caused the Idler to migrate inward. The belt not being true was caused by two things, the two pulleys were not in the same plane and the motor shaft was not parallel with the Idler Shaft. The alignment in the manual, which I hope has changed, was one of at least three contributors to the problem.

Even without the influence of the belt, I can see how the force applied by the SPT coupler spring combined with normal vibration could conceivably cause migration. My manual says that the eccentric clamp on the headstock should be "snug" and has various warnings about overtightening. I tighten mine the same way I did when it wasn't a PowerPro, which to my way of thinking is somewhat more than "snug." That said, the "Do not overtighten" warnings are sound advice, overtightening will break the casting.

- David

I like Bill Mayo's method of tightening to the point the split lock washer is fully compressed.

I do not know if that will be sufficient with a PP.

I have slowly tightened that bolt. Very slowly, a slight rotation at a time over months. The casting will crack if too much pressure is applied at once but the metal should reshape itself over time. Even then there's a limit.

A very fine line between tight and Pow!!!

stihlsawer wrote: ↑Sat Jan 11, 2025 1:03 pm A very fine line between tight and Pow!!!

I hope that is not from recent experience!!!

JPG wrote: ↑Sat Jan 11, 2025 5:19 pm

stihlsawer wrote: ↑Sat Jan 11, 2025 1:03 pm A very fine line between tight and Pow!!!

I hope that is not from recent experience!!!

Not from my shopsmith, but when I was young and too lazy to get a torque wrench!!

JPG wrote: ↑Fri Jan 10, 2025 9:32 am I like Bill Mayo's method of tightening to the point the split lock washer is fully compressed.

I do not know if that will be sufficient with a PP.

That's great advice for lock or crush washers.