Brake centering
 

I'm doing my 1st brake job on the front of my 1930 fordor. I welded the roller track and ground the hight right at 1.312, the front shoe is high by about .090. Is it normal to have to remove that much material from the roller track to center the shoe. All the parts are new and measure up correctly.

Re: Brake centering
 

Bob, where did you get that number from? Exactly where did you measure from because that number is not in any of my notes.

Oh, and welcome to Fordbarn. (The best place to get accurate answers to your questions!! :D)

Re: Brake centering
 

Thanks, It is from Les Andrew's book , I think I have the dimension correct. From the rivet to the roller track surface. I don't have the book with me. 1 5/16"

Re: Brake centering
 

He says to bend the track to adjust. I'm not going to bend it .090

Re: Brake centering
 

Unfortunately, his measurements are incorrect. Below is a PDF file that I made which gives you several references to verify the measurements with. The lower pic is from the original print that shows Ford's specifications. While it is not the 0.090" as you are finding, there is likely the majority of your issue.

Another FWIW, if all the other brake components are to Ford's specs, and the tracks are correctly sized and located, then I find a centering tool is unnecessary.


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Re: Brake centering
 

That's very helpful. I'll check this out after work. Thank you very much.

Re: Brake centering
 

After further thought. I think Les' measurement is from the rivet head which is probably the difference.

Re: Brake centering
 

Actually, in the PDF that I uploaded, it shows the measurement is taken from the lower portion of the hole. In my calculations, I show where that hole in the track is supposed to be 0.260", and so I factored in ½ of the hole's diameter and added to his specification. Then I compared Les' number to the Ford specification which is where I got the 0.055" discrepancy.

Re: Brake centering
 

Do not Bend the tracks. I replaced all tracks, no welding, no grinding no guessing. What is the hardness of weld over replacement tracks?

Re: Brake centering
 

The hardness is comparable to the original. I understand the dimensions and all that is going on, I've been a precision machinist for 40 years. I just have to figure out why this is not centered. I have a set of replacement tracks I could through on but the dimensions of them are the same as the ones I welded. I I just got to figure out what's up.

Re: Brake centering
 

A word on brake shoes.
IMHO

In the past Raybestos sold a tool for bending the brake shoe core to arc the brakes to fit the drum. This tool was called Raybestos Kam Way. See attached page from a Raybestos catalog.

So if you are using old brake shoes you may have a problem if the shoe was bent to allow the shoe arc to match the drum in its past.

Bending the shoe will solve one problem; the arc of the lining will match the arc of the brake surface on the brake drum. But it will create another problem. For the sake of clarity the following discussion relates to the front brakes, for the rear brakes the brakes are rotated 90 degrees.

Bending the shoe will allow the arc of the lining to match the arc of the brake drum. But when the shoe is bent the distance between the holes for the roller pin and the hole for the pin that holds the brake adjusting shaft is now changed.

If the shoe was bent to decrease the arc of the shoe the distance between the two holes was reduced and the shoe will sit lower on the roller track and the arc of the shoe will no longer be concentric with the arc of the inner surface of the brake drum.

If the shoe was bent to increase the arc of the shoe the distance between the two holes increased and shoe will sit higher on the roller track and the arc of the shoe will no longer be concentric with the arc of the inner surface of the brake drum.

I no longer will use old brake shoe cores. Randy Gross has all his brake shoe cores checked and if they are bent he bends them so they are correct or does not use them.

Re: Brake centering
 

The shoes are new molded linings from Mac's.

Re: Brake centering
 

Well, after taking the backing plates and all the components into work and measuring everything, the only thing I could see that was off at all was the roller track needing .015 to come off. So I cut the .015 of on the Bridgeport. Well this morning I put things back together and voila, It all works now, the shoes are on center. I can't believe that was all the problem. Thanks for all the thoughts, especially the print, it helps to talk things through with people.

Re: Brake centering
 

The 1-5/16" dimension in Les book is to the shoulder of the stud, which I believe is 3/8" diameter. 1.499 minus half of 3/8 (3/16 or .1875") is 1.3115", which is .001" less than 1-5/16".

Re: Brake centering
 

BTW, in one of the Service Letters books, the Branch stated that dealers asked to buy the little plate to avoid replacing the whole backing plate. No luck, said the Branch, as the plate went through some kind of adjustment after installation, so the dealer had to replace the entire plate.

Re: Brake centering
 

I kinda see your point however two things, ...

The name of the A-2226/A-2037 part is called a 'Brake Shoe Retracting Spring Stud'. The instructions in Les' book states the measurement is taken from the Spring Stud/Rivet. Why even mention the word rivet if that is not what he meant to measure from, ...and why show the measurement to the edge of the hole instead of the stud?

Second, this has been an ongoing issue of confusion for years. That is why I made the PDF so people could understand what the correct dimension should be and where their error is when they follow his instructions. Other people have interpreted this measurement the same way as the OP did here. As mentioned above by Eric, even Ford did not allow the A-2017 to be a service item simply because it takes a fixture to align those where there were 4.622" from the centerline of the spindle to the top of the track glide surface. If you do not have a fixture that locates the tracks correctly, it is very easy to miss the measurement, -or even worse, rivet the track on at an angle and not parallel.