Brake Shoe Lining Beveling?

I have seen posts on here where guys spoke about beveling the edge of their show linings (1939-1948) but not sure why. Are you guys getting drag or binding, rubbing or something? The reason I ask, I put my drum on full way and tighten up, its virtually stuck, I loosed the nut, move it back less than 1/4 inch, it spins the way I expect it should, slide back down into tightenend position, almost impossible to turn. So in my estimation, maybe the shoes are binding or rubbing as it gets to its end position. Could the lip of the drum be rubbing on backing plate? I dont hear any tell tale rubbing other than the shoes. Who knows, maybe I am nuts. Any ideas fellas?

 

I beveled the edges on shoes it was told it was to try and prevent squeaks.

 

If you did not have the drum turned (machined) you may be hitting the lip
on the drum.
At one time shops used to "arc" the shoes to fit the drum after turning the drumb.
That was so the shoe would have full contact right away.
There was a seperate machine for doing this.

 

You might try "arcing" the brake shoes. The machine shop that lined my shoes (NAPCO drums with Studebaker shoes), arced them with a machine. It isn't sophisticated, just a modified sander/cutter that cut the shoes in an arc. When I initially checked the arc of the brake shoes against the drum, there was a gap at the mid-point. After the arching they aligned perfectly. It made a big difference for me because of the tight tolerances.
don

 

I wish I could find a local shop to arc my shoes on my Buick brakes on 32 Ford. It seems the danger of Asbestos dust has eliminated everyone around here that did it.


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I always chamfer all four ends.
One way is the measure 9-3 oclock 1/8 less then drum.
When you put the drum on if its hits top, grind more off about 1/2" 3/8 to first rivet hole. In small shops that was done that way.Get a chance to die take it.

 

It was called heeling and toeing the brake shoe. The beveling at the top and bottom of brake shoe created a smooth shoe contact on the drum in foward braking and a reverse brake. Was a final step when arcing brake shoes.

 

I believe that arcing the shoes is the correct way to do it. But the first brake job I ever did my Dad took the shoes over to the bench and cut a bevel on them with a wood rasp, then took some 320 paper on a block and smoothed and rounded the bevel.

 

I believe your brake issue is created when the outer edge of the shoe contacts the brake drum inner edge. Since you say that the drum spins fine when you loosen the axle nut this to me means that the drum is setting and rubbing against the outer edge of the brake shoes. Take your drums off and look for a polished spot right at the junction of the brake surface and the inner edge of the drum. New shoes are just a little wide and drag on this edge if the drums braking surface have not been turned wide enough. If you have limited tools you can fix this by sanding the edge that rubs down on a belt sander, narrowing the shoes by about 1/8" or less or have the drum turned wider to remove that lip.

 

The outside edge of the shoe is probably touching a slight wear step in your drum on its inside edge. Wherever you suspect it's binding, scuff some blackboard chalk on the shoes. Set the adjustment loose and gradually adjust the shoes outward, rotating the drum. As soon as a slight binding begins and the drum gets a bit tough to turn, pulll it off. Look at your shoes and you'll see where the drum has scuffed the chalk away.

Typically where shoes are binding the shoe surface at that spot turns a glossy black. Easy to see. The chalk helps. Truing up the drum and cleaning up that inside step is a good idea. Correctly arcing the shoes is well worth it. Good luck.

 

Found some one local that bends the shoes to conform to the drum. Does a lot of model As. He said it really makes a difference. What do you guys think?
No luck finding some to grind-arc shoes here. Old motorcycle trick is to contact cement 80 grit paper to drum, then spin the wheel by hand and slowly applying brake to sand the lining to match the drum. I don't how well this would work on a auto.



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are the shoes to wide for your drums? i do not think arcing the shoes will help your problem but i have arced shoes by just placing sand paper inside the drums and rubing the shoes back and forth, no glue the paper didn't move at all for some reason.

 

I Ago don't have the problem. It was the OP. My thought was since I can't find any one local to arc new shoes, I was looking for another way. My 32 with Buick brakes work fine. I have12,000 miles on the car now and the shoes are bedded in now.



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