Shopsmith Forums

How hot is acceptable for the drive sleeve/bearing area of the headstock on a 10er to get when running at the fastest speed?

I just replaced the drive sleeve bearings with factory OEM Fafnir bearings, and my belt is not too tight (currently a Fenner Powertwist belt). The install went well, and I was very careful to not damage the new bearings.

I also used Aeroshell 6 grease for the spline/drive sleeve interface, which I wasn’t sure if that’s an acceptable lubricant for those parts.

The only other thing that I changed is the headstock pulley which is heavier than the original, so perhaps it’s composition is more heat conducive than the original?

***UPDATED 09/07***
I did quite a bit of testing on the machine last night. I had remembered that the original outer drive bearing’s outer race would actually spin in the headstock on occasion indicating a loose fit. The old drive bearings removed without any resistance at all, and the new bearings installed just as easily. I wonder if my headstock drive bearing housing was machined a little to large. Once the new bearings were installed, I held the drive shaft (pulley side) and attempted to lightly move it up and down. I could actually hear and feel slight up/down movement. I tested this with the original bearings last night (on my finger, not reinstalled on the shaft) and they had this same play in the headstock.

With the belt removed, I placed slight upward and downward pressure on the drive shaft while extending and retracting the quill with light return spring pressure applied. I found that I could actually lightly bind the retracting quill with downward pressure on the drive shaft, but not using upward pressure. I decided to sacrifice a .002” feeler gauge blade and shimmed the bottom of both drive bearings. The bearings still installed using hand pressure only, but did provide slight resistance. This shim removed all of the play in the drive shaft, and I could no longer bind the quill with downward pressure on the pulley side of the drive shaft. I reinstalled the belt and ran it for a bit, and the machine ran quieter! I let the machine run for a few minutes and it appeared to not get as hot as before.

I also replaced the aeroshell 6 grease with white lithium on the spline/drive sleeve interface, but I do not believe the lubricant had anything to do with the heat.

I’d be interested to hear how others bearings replacements went. Did your new bearings just slide right into the headstock without any resistance, or have a more snug fit? If most others had a snug drive bearing fit, then my shim job is for sure needed and justified.

Thanks!

How hot is it getting? Too hot to touch? Do you have an IR thermometer to check it with?

Belt alignment good?

edma194 wrote:How hot is it getting? Too hot to touch? Do you have an IR thermometer to check it with?

No IR unfortunately. I can leave my hand there comfortably. I’ve only noticed the heat because of swapping out my bearings and purposely putting my hand there to check. I wish I would have thought to check this prior to swapping the bearings, maybe it’s normal??

JPG wrote:Belt alignment good?

Belt alignment is perfect. I took a lot of time to make sure of that.

Tell me about 'Fenner power twist). Whazzat???

JPG wrote:Tell me about 'Fenner power twist). Whazzat???

The link v-belts: https://www.rockler.com/1-2-power-twist ... O9EALw_wcB

Supposed to smooth out vibration and not form “memory”. They were great on my table saw and bandsaw, so I slapped on on my Shopsmith too about 15 years ago. I do have a conventional belt on order as I’ve recently found that the link belts may increase wear on the aluminum pulleys. I just got one of Skip Campbell’s machined headstock pulleys and was so impressed, that I ordered a matching motor pulley. Want to keep nice, so figured I’d dump the link belt, (which does show some impressive aluminum transfer).

nv10er wrote:
The link v-belts: https://www.rockler.com/1-2-power-twist ... O9EALw_wcB

V-belts and pulleys get hot. I'm guessing a link belt has more friction losses and gets hotter. If it's not too hot to touch then I'd guess no more than 160F, does that sound right? It's not dangerously hot and probably well within the limits of that bearing. I don't have a running 10E to compare to, maybe the other guys can give one a feel.

edma194 wrote:

nv10er wrote:
The link v-belts: https://www.rockler.com/1-2-power-twist ... O9EALw_wcB

V-belts and pulleys get hot. I'm guessing a link belt has more friction losses and gets hotter. If it's not too hot to touch then I'd guess no more than 160F, does that sound right? It's not dangerously hot and probably well within the limits of that bearing. I don't have a running 10E to compare to, maybe the other guys can give one a feel.

Correct, it’s not uncomfortable at all to leave my hand there.

If you can leave your hand on it than it should be okay. I have never really noticed any problem with them getting to hot on any of my Model 10 restorations. I run them a while after they are reassembled and aligned. I have never put the twist link belts back on a finished restoration although a couple of them have come with that kind of belt. Changing to a V belt should help a little. That wear from the power twist belt may be adding friction heat. You can use a cogged type V belt which grips the pulleys a little better than standard V belts if you prefer.