Shopsmith Forums

I was trying to clean and lubricate the speed control of my (new to me) Mark V 500 and as I was cranking the speed up it popped and rattled quite a bit.

I’m pretty sure the circled part in this photo should be pushed toward the right and into the shaft there. Did I break it? Do I need to replace it? If so, what is the part called so I can order it? If I can fix it, what do you recommend as to how to get it back in there?
Also, when do you know if you need to replace the belts? I’m not sure how old these are. They seem in good shape but very stiff. I’m in AZ so rubber belts (and windshield wipers) dry out quickly.

It looks like your control sheave bearing came out.
Here is a video that addresses this bearing.

https://www.youtube.com/watch?v=lm86LKc4ufg

You might be able to get it back in place if the bearing is still good. There is a seller on eBay that sells a replacement bearing if your bearing is dry. Please note that replacing this bearing often cracks the sheave housing.

https://www.ebay.com/str/bandsawtirewar ... 1763958015

You can purchase a new sheave and bearing combo form the mothership ( I believe it is one of their most commonly replaced parts)

https://www.shopsmith.com/service/mostf ... dparts.htm

More important is the cause. I suspect inadequate lubrication(oil) on the floating sheave(motor shaft). That loop should not be 'pulling' on the bearing.(assuming only changing speed control while pulleys rotating)

Belt dressing/conditioner will help dried, stiff rubber belts.


Is it possible you were cranking up the speed with the pulleys NOT rotating?

I recently ran across this problem when giving a later Model A-34 Jig Saw a thorough overhaul. The Upper Chuck Assembly was previously trapped within the Spring Cylinder Assembly, but it is now free to spin.

sneaky link deleted - user banned

These are two different problems. The OP has a problem inside the Headstock of a Mark V whereas you are describing a problem with the Upper Chuck of an A 34 Jig Saw for a Model 10E and 10ER being stuck. Something I have had the displeasure of having to deal with in one of my restorations.