purrin like a kitten

[8iowa]

My new idler shaft arrived yesterday. It was identical to the one shown by Dusty in a previous thread, with the two bearings instead of the water pump bearing with the groove in the middle.

After installing this shaft with a new idler sheave, the Headstock now runs smooth and quiet. since there is no place for the set screw to tighten against, on older headstocks, a new excentric with the stop screw is also required.

[dusty]

My new idler shaft arrived yesterday. It was identical to the one shown by Dusty in a previous thread, with the two bearings instead of the water pump bearing with the groove in the middle.

After installing this shaft with a new idler sheave, the Headstock now runs smooth and quiet. since there is no place for the set screw to tighten against, on older headstocks, a new excentric with the stop screw is also required.

The new eccentric, shown in my posted images, is identical to the eccentric that came in my nearly twenty year old Mark V. So my question - is there a difference between an "old" eccentric and a "new" eccentric other than age? If yes, could you post a picture?

[billmayo]

The new eccentric, shown in my posted images, is identical to the eccentric that came in my nearly twenty year old Mark V. So my question - is there a difference between an "old" eccentric and a "new" eccentric other than age? If yes, could you post a picture?

Yes, all the eccentric bushings are interchangeable. Shopsmith has used several different versions of the eccentric bushing. Yes, I have some of the older eccentric bushings with the split at the thin part. I use a #8 body washer to prevent the eccentric bushing and/or the idler shaft bearing from extending past the end of the headstock housing. I have been using the split eccentric bushing without any set screw in my rebuilds for the past few years. I find the #8 body washer and machine screw (5/16" X 1 3/4") that tighten the headstock casing to the eccentric bushing is all I need to prevent the idler shaft and/or eccentric bushing from moving. This allows me to align the Gilmer/Poly-V belt for straight tracking on the idler sheave pully and the drive sleeve pulley if it is needed.

I actually sawed a split in some older eccentric bushings that did not work well. The eccentric bushing split closed up some and it was very difficult to insert the idler shaft bearing into the sawed eccentric bushing.