Skil belt rub

General Discussion
1

Paging Pete! Hahah (you need a bat signal haha) 

or anyone that’s had this happen before. 

Just picked up another skil and it’s got a belt wander.  I spin it one way and I wanders towards the planer body, spin it the other way and it wants to come off the Pullys. I just swapped out the bearings but I could see evidence of the belt rubbing before I did this. 

Shafts don’t have any (visual) wobble to them (meaning they are straight). I suppose I can chuck em up and stick a dial on them but lack of visual wobble seems like they should be fine. 

I Spin the motor pully and it did the same thing (thought maybe the teeth were bad) 

What am I missing? 

Bad belt?  

I pulled up a parts diagram and I got everything in there haha. 

Seems like they are out of alignment some how??? 

SOS!! 

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2

Common to all Skil’s.  Toothed belts were a new thing in the early 1950’s and prone to stretching.  The sprockets are intentionally aligned so that the belt moves inwards and doesn’t fly off as it stretches.  If you rotate the motor sprocket in the opposite direction the belt will move outward. Skil probably figured by the time the belt started wearing against the coverplate it was time for a new belt anyhow.  The old factory service documents I have show a fix for this by adding a second washer under the motor sprocket which does work.  However the edge of the washers causes side wear on belt so it gets narrower as it wears.  My fix is to use a special washer which I make that has an edge-bevel and larger OD.  Works like 1/2 of a V-belt pulley which keeps the belt tracking straight. The post for the belt cover has to be notched though and the motor cover removed.  I will put one on next time you’re in the area, just email me.

Anyhow, tooth belts have come a very long way since the first Skil’s, used on everything from precision robotics to drive belts on Harleys.  Instead of aligning the sprockets like Skil did, modern sprockets have flanges on each side like a V-belt pulley.  That’s how I came up with that beveled washer. 

3

Thanks for the reply and offer Pete. I’ll keep in touch. 

Ill try a new belt in the short term. I’ve ran a few old lathes that used the same directional spin on the belts but none that would end in rub. 

i might try a little Teflon washer on the cutter and motor as well. 

Ill get with you next time I’m down south. 

4

You can’t really shim out the cutter sprocket due to the hub on it, and you don’t want to anyhow.  If you move the cutter sprocket out it’ll throw the belt, it’s the motor sprocket that has to be shimmed.  If you want to try washers under the motor sprocket I’ll mail you a couple just let me know.

5

Its been a while since I’ve had it apart but I’m almost positive the newest of my 3 planers has a mylar washer that is slightly bigger than the outside diameter of the sprocket that sits between the sprocket and the housing to prevent the belt from rubbing the body.