Brake Shoe Centering

I've never heard of cutting a hole in the brake drum will help in centering the brakes. I've heard of cutting a hole in the front drum to release the old lever type floaters that are no longer made. The old lever type floaters when used with worn out drums could go past the point of return if brake adjustment got too loose. In such cases a hole in the right spot on the drum would allow the use of a pry tool to lift the floater .
 
I think the idea of cutting a hole in an old drum is to give you something to measure. The way it was told to me was, you can use feeler gauges to measure between the shoes and drum to make sure your adjustments are right and the shoes are the same distance from the drum. I was told the centering tools just do the same thing. I'm in the dark here looking for the light switch!!
 
I think the idea of cutting a hole in an old drum is to give you something to measure. The way it was told to me was, you can use feeler gauges to measure between the shoes and drum to make sure your adjustments are right and the shoes are the same distance from the drum. I was told the centering tools just do the same thing. I'm in the dark here looking for the light switch!!

You're correct.
The only thing to worry about is if the bottom of the rear axle bearing surface has a lot of wear then the drum will be closer on the bottom when the car is off the jack stands, and the wheel is supporting the car.
 
Thanks for the heads up, Tom. I'll put some lift under the axle nut as I do the checks.
It's info like that where this site can't be beaten.
 
Thanks for the heads up, Tom. I'll put some lift under the axle nut as I do the checks.
It's info like that where this site can't be beaten.

You can't center by using an unsupported rear axle, as the axle can move around in the housing.
The rear wheel hub and bearing supports the axle.
 
Tom, I figured that by putting a jack under the axle nut, I could lift the axle to simulate the car's weight on the axle, which is where it is when the car is on the ground. It would lift the axle relative to the housing to the position it would be in when the car has its weight on the wheels.
I thought it would be easier than putting the wheel on and lowering the car each time. I guess it will have to be adjusted and checked a few times to get it right so this would be easier.
What do you think?
 
Synchro909, someone made a tool to check the centering by using a PCV pipe and thin rod. It slips on the bearing area of the rear axle and should do the job perfectly.

I used my MIG welder and Dremel to repair the worn tracks. I think the square adjusting pins are a good idea. They also have the added benefit of a larger wear suface than the head on the round pin.
 
Tom, You said " You need a centering tool to center the rear brakes. I got one from Bratton's." I've heard that cutting a hole in an old brake drum can be used to centre the brake shoes instead of one of those tools. I haven't done a reline on a Model A before but do you (and others) think it will work. Seems viable to me but like I said, I haven't been there.
Purdy, I take your point about centering them up and down. Looks like the welder will get some use (again)

Here's what I am using for a centering tool. I used 2" PVC and a piece of #8 copper wire.
 

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You're correct.
The only thing to worry about is if the bottom of the rear axle bearing surface has a lot of wear then the drum will be closer on the bottom when the car is off the jack stands, and the wheel is supporting the car.

Along the same lines, I have always recommended adjusting the rear brakes with the wheels on the floor and pushing the car by hand to feel the drag. If the rear brakes are adjusted with the wheels in the air, as on jack stands, the brakes will be too tight when the wheels touch the ground. Even if the axle housing bearing races don't show any wear, there will be enough slack in the rear hubs and roller bearings to effect rear brake adjustment in most model A's unless all of the parts are new .
 
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