I was doing a little turning on my 83 model 500 'B' head-stock. Advancing the speed as the wood was reduced in size, I heard a snap, pop, and the sound of a small piece of metal landing on the bottom of the motor housing. The unit remained running but the speed control wouldn't change the speed. Aggravated a small bit . (I had rebuilt this about six months ago). I took the head stock apart and found a seized bearing on the end of the Control Sheave where the retaining loop attaches.
I can find no reference to this bearing anywhere. My better half and I finally discovered a number on the bearing itself NSK 635Z. (Thanks to a magnifying light and two sets of eyes both of which are north of 64).
I did take pictures with my phone if we need to post. Has anyone replaced this bearing, or did they replace the entire control sheave as is documented in the parts lists?
Any thoughts?
Don
In the Florida Panhandle
Give me a sense of humor, Lord, Give me the grace to see a joke,
To get some pleasure out of life and pass it on to the other folk.
— J. Maurus
If it is the little bearing with the clip on the end it can be replaced. I replaced mine myself last year and so far, so good. I don't think that Shopsmith sells that part, but you can find them on ebay. You need to re-set the bearing (might have to clean up or deepen the receiver a bit ) and then pean it in place to hold it on the shaft. There are posts on this site that describe the process. This bearing usually pulls out only if the sheaves are not well oiled.
In my opinion, it is best to buy a new control sheave from Shopsmith. Your bearing froze up because of inadequate lubrication. Every 10 hours of operation You should run up to high speed and drop several drops of oil into the shaft's hole. Two drops just aren't enough. Don't be afraid to use more. The extra oil will serve to lubricate that small bearing.
Also lube the movable sheave shaft next to the motor sheave. When properly lubed, the movable sheave can be smoothly slid out (compressing the spring) with your hands. Don't let that sheave bang into the motor sheave.
Octogenarian's have an earned right to be a curmudgeon.
Chuck in Lancaster, CA
Thanks guys. I have ordered a bearing and will try that first. Being a bit cheap I figured 13 buck compared to fifty (counting shipping) was worth a try. I do, have and continue to oil this ol' machine, but obviously not enough in this area. Again thanks for the replies and did I mention my wife thinks I'm cheap?
Don
In the Florida Panhandle
Give me a sense of humor, Lord, Give me the grace to see a joke,
To get some pleasure out of life and pass it on to the other folk.
— J. Maurus
Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
I remember now how I replaced the bearing! I chucked the shaft in my Delta lathe and removed about 1/16 inch of the end of the shaft with a carbide cutter. Then with the same cutter (square), cut the bearing recess about the same much deeper. That gave me a clean area to stake the bearing. Actually quite easy.
. (I had rebuilt this about six months ago). I took the head stock apart and found a seized bearing on the end of the Control Sheave where the retaining loop attaches. 
