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Brake Shoe Arcing

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Brake Shoe Arcing


Post by King » Tue May 03, 2011 9:52 pm

Hi All

Scored new brake shoes for my 51FL at Oley. Want to install soon but I'm a bit confused about "arcing". I noticed Palmer has a write-up on the subject but it is a bit cryptic. Anyone know the correct proceedure? The knowledge base is mum on this.


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Re: Brake Shoe Arcing


Post by Cotten » Tue May 03, 2011 10:38 pm


Machines designed to sand the lining to match the arc of the drum used to be a standard in any auto machine shop.
But the hazardous nature of the airborne debris has made them quite scarce these days.

The manuals usually just mention putting a healthy chamfer upon both ends.

Some folks go to the trouble to fixture the backing plate with shoes installed to a lathe faceplate for turning.
But most of us just look at the contact spot, and make it bigger and bigger with a rasp.
Some folks slip a strip of emery between the drum and lining to somehow sand them to mate.

Good luck, and please treat the debris as toxic, whether asbestos, or not.

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Re: Brake Shoe Arcing


Post by Bigincher » Wed May 04, 2011 1:08 am

An auto machine shop or brake/clutch shop ought to arc your shoes to the drum for an extremely minimal fee. They are set up to do it, have all the right equipment, and can have it done before you can even think about how to accomplish it yourself...!
I like to do as much as I can on my old machines, like all of us, but sometimes it makes no sense at all to fuss around with some things--- let the professionals help out..!
And on the other hand, I love barnyard engineering...!!

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Re: Brake Shoe Arcing


Post by c.o. » Wed May 04, 2011 1:36 am

Great timing on this thread.... I'm waiting for a set of shoes to show up in the mail.

George Greer
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Re: Brake Shoe Arcing


Post by George Greer » Wed May 04, 2011 4:11 am


Where/how do you always come up with those neat toys??

On my WLA, once I found a NOS rear drum, I took sticky sided sandpaper stuck to the insides on the drum, put shoes on backing plate, installed the assembly onto the drum and with a little pressure on the actuating arm for the brakes, just sanded round and around till the shoes looked evenly worn from the sanding...

Cleaned up with MEK.... Chamfered leading and trailing edge of brakes. The shoes perfectly match the drum.


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Re: Brake Shoe Arcing


Post by Cotten » Wed May 04, 2011 1:37 pm

George Greer wrote:Where/how do you always come up with those neat toys??

I have been a scrounge all of my life.
This piece was "de-commissioned". But a bearing, and an extinct emerypaper roll, would make it operable. It would need the shoe carriage to be re-engineered, however, to hold front brake shoes.

Front shoes are the ones that need it.


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