Shopsmith Forums

JPG wrote: Tue Dec 29, 2020 5:32 pm HOW does it 'ride high' unless it is 'bent'?

Because the hub is cracked and bent outwards allowing the end of the key to come out of the slot???

Assuming it is secured at the 'interior' end and sliding in a straight keyway on the shaft the interior end SHOULD cause a straight key to be tight to the bottom of the keyway at the 'free' end. It ain't so it must be bent.

"Key' here is that it IS secured at the interior end.

JPG wrote: Tue Dec 29, 2020 5:48 pm Assuming it is secured at the 'interior' end and sliding in a straight keyway on the shaft the interior end SHOULD cause a straight key to be tight to the bottom of the keyway at the 'free' end. It ain't so it must be bent.

"Key' here is that it IS secured at the interior end.

If you say so but since the hub is cracked and bent outwards at the free end of the key it will allow the free end of a straight key to come out of the slot even if the captured end is held in place. The crack looks to be all the way down the the "captured" end.

The fan sheave setscrew should hold the key in place under normal conditions. Was it in good shape and was it tight? I'm not sure about a fix for that crack, I think the spring needs to compress and expand smoothly over any repair. My first thought was replacement, but if something like a thin wall steel sleeve would press on that seems like a permanent fix.
Note - my only round wire spring is in my attic so I didn't confirm this. The newer flat wire springs don't leave much room for a sleeve without some machining, but I think the round wire results in a larger ID for the spring that would clear a sleeve repair.

IIRC, some early floating sheaves did not have the hole for oiling. This would be a good time to add it if you don't have it. If you go with a sleeve you'll want to drill an oil hole in the sleeve as well.

- David

After cleaning away the grease on the bottom fan blade sheave I found the set screw. It must have gotten loose to cause the scraping against the housing, as I didn't have to loosen it to remove the sheave. I'll be sure to tighten it when I reinstall the sheave.

DLB, you're right about spring clearance regarding the collet repair. I hadn't considered that, so my hose clamp idea won't work. Too high of a profile on it. I only have about 5mm of clearance for my round wire spring. Maybe some some duct tape instead (just kidding).
MB

DLB's suggestion about a steel sleeve made me remember this thread about using a copper sleeve to repair the control sheave posted by redleg.

viewtopic.php?f=10&t=19238

Perhaps the same kind of thing would work for you? If you can't find a sleeve of the exact inner diameter needed (copper or steel), perhaps a slightly larger sleeve would work, with JB Weld to make it secure. Or, a slit in a slightly larger sleeve to remove some material and then use hose clamp to temporarily apply pressure while JB Welding and re-forming to circular shape of cracked hub.

I like the sleeve idea. If I can't find the right dimensions for it at the hardware store, I'll try the JB Weld technique.
Thanks!
MB

Here are a couple of charts for electrical conduit and copper pipe standard sizes with I.D., O.D., wall thickness information, in case this will help find a proper size sleeve.

For copper, also keep in mind that fittings will have an I.D. just slightly larger than the O.D. of the same nominal size pipe.

Many thanks! I just took my sheave to the hardware store and picked out a piece of plumbing tubing and cut it to length. It seems to work well, and the main spring fits over it nicely. I got the motor housing all reassembled, and I'm astounded how well it runs now all cleaned up and lubricated. I reinstalled the sheaves with the new coller and key fits just fine. I bought a slightly oversized washer to backup my snap ring at the end of the axle, so once I rectify that I'll post a photo of the completed repairs when that's all done.
MB

FWIW the set screw does NOT control the fan sheave to motor housing spacing. That pesky collar between the bearing inner race and the fan sheave does that.