Shopsmith Forums

I've just started really using my old Mark V recently, but tonight it suddenly started making a grinding noise and the speed control was stiff as I hurried to slow it down and turn it off.

It appears to be rubbing at the end of the shaft (idler?) there against the, uh, speed control doohicky (quadrant assembly?). Taking the cover off, I found a single bearing, about the size of a BB, at the bottom - not sure how it's related actually.

So, can you tell me what the problem is?

I do have some mechanical background, so I'm not really afraid of working on this but I'd like to get an idea of what I'm dealing with since the innards of this machine are all new to me.

I received this in 1996 as a gift from the original owner and have schlepped it around since waiting till I had time to use it. I doubt the PO lubricated or maintained it much, and though I do lubricate it before using it, that occurrence has been rare up to now.

Thanks,
Nathan

There should be a bearing in the end of the 'snout' of the 'control sheave' where you are indicating the 'rubbing'. That bearing should have a 'button' inserted into the inner race of that bearing. The button should have a hole drilled through it(perpendicular to the axis of rotation) and a roll pin in that hole. The spring(square loop) that goes over the 'quadrant' gear arm is inserted into the roll pin. The quadrant gear end has a spring like piece that rotates on the spring(when positioning it onto the quadrant gear). I cannot tell from your pix the condition of the bearing. It is possible it is seizing and that is creating the noise. Since the loop appears to be intact, merely getting some oil into that bearing MAY cure the noise.

I would recommend a thorough cleaning and lubrication of the sheaves. See sessions 11,21 thru 24 here.

JPG40504 wrote:There should be a bearing in the end of the 'snout' of the 'control sheave' where you are indicating the 'rubbing'. That bearing should have a 'button' inserted into the inner race of that bearing. The button should have a hole drilled through it(perpendicular to the axis of rotation) and a roll pin in that hole. The spring(square loop) that goes over the 'quadrant' gear arm is inserted into the roll pin. The quadrant gear end has a spring like piece that rotates on the spring(when positioning it onto the quadrant gear). I cannot tell from your pix the condition of the bearing. It is possible it is seizing and that is creating the noise. Since the loop appears to be intact, merely getting some oil into that bearing MAY cure the noise.

I would recommend a thorough cleaning and lubrication of the sheaves. See sessions 11,21 thru 24 here.

Great, thanks - I'll check those sessions out ASAP. Hope this'll do it, much better than the shopping list I was envisioning

After cleaning and oiling this puppie, if you still have any unwanted noise at high speed - I would suggest that you perform a "high speed stop" adjustment. It appears to me that the Control Sheave is too far out (thus rubbing the porkchop).

Me thinks that the BB in the bottom of the motor pan may be from the bearing in the end of the control sheave. Probably some more of them hiding in the sawdust.
Bill V

wa2crk wrote:Me thinks that the BB in the bottom of the motor pan may be from the bearing in the end of the control sheave. Probably some more of them hiding in the sawdust.
Bill V

Finally had time to get into the headstock and it looks like you're right. The bearing at the end of the idler shaft had come all apart. You can see in the attached photos - part of it is still in the shaft, the retaining loop was still around the quadrant assembly.

Is this something I can replace myself? I don't see the bearing listed separately in the illustrated parts breakdown, but I have seen it for sale on ebay.

Your control sheave bearing is toast per your last pics. You will need a new control sheave or purchase just the bearing part. I have seen a listing on Ebay recently for just the bearing/button part. This may also be available direct from SS but I have not checked the parts breakdown to verify. Doesn't look like the bearing itself is available seperately through SS but you can purchase the control sheave assy. complete.


515556 Control Sheave Assembly (incl. 110-112) 49.26

And here is the Ebay listing for just the bearing part

SHOPSMITH GREENIE SPEED SHEAVE BUTTON,BEARING AND LOOP

Yep, just figured out that I was incorrect earlier - it's bearing in the control sheave, not the idler shaft. Wow, fifty bucks for the whole new control sheave assembly. I might consider buying just the bearing and doing that myself after all - although it looks like it's not simply pressed into place. Looks as though it's pinched in there.

nsmith01tx wrote:Yep, just figured out that I was incorrect earlier - it's bearing in the control sheave, not the idler shaft. Wow, fifty bucks for the whole new control sheave assembly. I might consider buying just the bearing and doing that myself after all - although it looks like it's not simply pressed into place. Looks as though it's pinched in there.

The 'word/process' is swage. Pinched is a good description! Once the old bearing is 'knocked' out, the new bearing can be 'peened' into the 'snout'. Not as good as 'original, but servicable.

The Control Sheave Button is not available from Shopsmith. Ebay seller "tristateauto" are making and selling many unavailable parts that I am buying from them. I have been very happy with all the items (belts, idler shafts, Control Sheave buttons, etc.) I have received for them.

The Ebay item REPAIR YOUR SHOPSMITH MARK V SHEAVE BUTTON, BEARING, LOOP is just what you need if you have some method to secure (stake, my word) the bearing. I use a small coal chisel with the sharp cutting edge ground off for staking.

I am finding the bearing depth in the end of the Control Sheave can have different depths. Many times, there is not room to fully secure the bearing. I have been machining this depth up to an additional 1/16" to allow room for the staking. I always use LocTite to help secure the bearing in the end of the Control Sheave.