Shopsmith Forums

Put it all back together after lubing the sheaves with some Tri-Lube and ran it from slow to fast and back to slow.

Started out in slow and worked OK, went to fast still OK, back to slow and it bound up before reaching the slowest setting.

It appears to me that your high speed adjustment is still off, allowing over rotation of the quadrant. There is a long setscrew in the speed control assembly that normally will be the high speed mechanical stop. If you observe where the belt rides in the Motor Sheaves, you'll see it moving outward as you adjust to a faster speed. At the fastest speed, the belt should still be down between the sheaves by about 1/8" from the outside. Whatever your speed indicator says at that point should be the fastest you use for now. (It is also the high speed point that you adjust everything to, but I'd defer the high speed adjust for now until you figure out the binding.)

Looking at your Idler from the outside of the casting, the eccentric should be outboard against a screw stop and the bearing should be outboard against another stop. Can you confirm both stop screws present and both parts against the stops? Also, doe the Poly-V upper belt look like it is running square and true to the two shafts?

- David

Because it acts like something is going on with the speed control, I removed the speed control quadrant and idler pully for inspection.

I found that I assembled the idler shaft clip / control quadrant spring incorrectly.

Being that the greenie parts are unavailable and I had to use the Mark V updated parts for my rebuild. Because of this I'm unable to assemble the idler shaft clip / control quadrant spring without inducing binding at the speed control quadrant.

The Mark V has a different P/N than the greenie. So I ordered the Mark V speed control assembly. Hopefully this will be the last parts I need to have a good operating machine and will fix the binding issue

The part numbers do change, but I'm not aware of any actual compatibility issue between the Greenie parts and the newer versions you have. In your last pic though, it is evident that the Worm Control Shaft (worm gear that drives the quadrant) is not in the proper position or not staying in that position. It should be held by a small snap ring that is visible when you remove the speed control handle. The shaft should have only a small in/out movement, yours is well inboard of normal. I'd look for that snap ring to be missing, broken, sprung, etc. but not in its groove. There should be a spring washer and a flat washer under the snap ring.

Other issues with the speed control are difficult to see in these views. The most important things are that the quadrant (aka porkchop) should be true to the worm gear shaft throughout its travel. Things that lead to problems with it not being true are wear in the holes, splaying of the legs, etc. Many of these issues can be fixed without replacement.

- David

Starting to make some sense(sorta).

First some terminology deviation observed. The idler pulley has two halves(sheaves) with a 'fixed' and a 'movable' sheave. The fixed sheave is referred to as the idler sheave and the movable one is referred to as the control sheave. The fixed sheave is captured on the idler shaft by bearing against a retaining ring(IS IT MISSING?). It is free to move away from the retaining ring but normally is forced against the retaining rung by the belt running in the idler pulley. In your pix and the description, the names were reversed(the 'upper' sheave is the idler sheave and the 'lower' sheave is the control sheave.

The speed control worm gear shaft is indeed moving in/out and it should not be so. DLB has identified what may be causing that. That needs to be corrected.

The pix showing the control sheave interfering with the speed control is the result of the porkchop allowing the control sheave to move too far away from the fixed sheave. The high speed stop is intended to prevent that. The worm gear shaft slop will not cause the interference since the shaft will be forced into the bore by the belt in the idler pulley.(control sheave being pushed by the belt) The worm gear slop likely is not happening under run conditions.

The too far open idler pulley(belt jamming) is likely the result of either the idler sheave mispositioned on the idler shaft or the idler shaft assembly including the bearing eccentric too far out of the headstock case bore.

The control sheave interfering with the speed control is because the high speed stop is not adjusted correctly.

So the things to check/fix are the retaining ring for locating the idler sheave on the idler shaft. I think it IS there or that 1/8" gap would not exist but DO verify it is there.

Determine why the worm gear shaft is free to move inward(missing parts?).

Last and only last do a high speed stop adjustment. It depends upon the other stuff being correct.

To my understanding the only difference between 'greenie' idler pulley parts and the current parts is the gilmer/poly-v belt hub on the idler sheave. In addition there is the new idler shaft bearing assembly(but that should not be relevant here).

One pix that has not been presented is of the idler shaft bearing/eccentric as it appears in the headstock bore. If not retained properly it could contribute to the jamming.

Nuf fer now.