Control sheave stuck

sbrana · Post by **sbrana** » Tue Oct 14, 2008 9:06 pm

In order to replace the control sheave on a 30+ year-old Mark V I removed the control sheave/idler sheave assembly, but I can't get the control sheave off the shaft. It's stuck. In fact, the two sheaves seem to be stuck together. How do I get the control sheave to move? I'm new at this stuff...and have essentially no mechanical expertise...so I'm not sure if I should be prying or twisting or tapping with a hammer or what.

a1gutterman · Post by **a1gutterman** » Tue Oct 14, 2008 9:13 pm

sbrana wrote:In order to replace the control sheave on a 30+ year-old Mark V I removed the control sheave/idler sheave assembly, but I can't get the control sheave off the shaft. It's stuck. In fact, the two sheaves seem to be stuck together. How do I get the control sheave to move? I'm new at this stuff...and have essentially no mechanical expertise...so I'm not sure if I should be prying or twisting or tapping with a hammer or what.

sbrana,
Glad to have you aboard. Sorry , I can knot help you, but I am sure that someone will, and soon! I will tell you that it is never a good thing to use a metal hammer on any ShopSmith part.

If you must tap, use a wood mallet or rawhide hammer.

charlese · Post by **charlese** » Tue Oct 14, 2008 11:04 pm

Hi sbrana! Welcome to the Forum!

I'll offer to be the first one to tell you what I'd do. Understanding that you now have the Idler Shaft, complete with both sheaves out of the machine and on your bench.

To get the two sheaves separated I would try to wedge a small tapered piece of hardwood between the sheaves. I'd use oak or maple or hickory. You probably make two or three stake like pieces and tap them into the spaces/grooves in between the two sheaves. If you use three stakes you can place them at equally divided spacing. (2 radians each) (6 radians in a circle) Tap/rap and wiggle - rap and wiggle - rap and wiggle, etc.

I would use a light mallet to drive (tap) the stakes.

Depending on the condition of the key and key-way, you may have to shell out for an entire assembly, like I did. But first get it part and see what you have.

Good luck!!

beeg · Post by **beeg** » Wed Oct 15, 2008 12:11 am

GOOD advice there Chuck. I'll just add, oil the shaft on both sides of the sheaves and between the sheaves too.

sbrana · Post by **sbrana** » Wed Oct 15, 2008 11:19 am

The wedges on either side did the trick. I did a little cleanup and lube on the shaft and the new sheave slid right on. I reinstalled the assembly and it works great. Thanks.

ryanbp01 · Post by **ryanbp01** » Wed Oct 15, 2008 12:27 pm

Welcome Sbrana! Keep us posted on your progress! This is a great group of people we have here.

BPR

sierraslim · Post by **sierraslim** » Mon Dec 28, 2009 4:38 am

I recently had the same problem of a control sheave and idler sheave stuck together, and found an alternative to the wooden wedges that also worked great.

I used a 3/8" rope as a wedge by tightly wrapping the line between the sheaves. I continued adding line until the rope extended beyond the outer edges of the sheaves. Then, I used a soft-faced hammer to tap the rope around the circumferance, adding loops as the sheaves began to separate. It took about a minute to nudge the control shaft free.

Like the wooden wedges, this approach did not cause any trauma to the sheaves or shaft.

JPG · Post by **JPG** » Mon Dec 28, 2009 12:59 pm

Now that that nightmare is past, remember to keep it from reoccurring!

Keep it lubricated(and the motor sheaves). Too dry can be a problem, too much and lt creates a mess inside the headstock which is a lot easier to clear out than what you just went through!

I had a devil of a time myself with a used one purchased for a 'spare'!:rolleyes:

Shopsmith Forums

Control sheave stuck

Control sheave stuck

success