Brake Adjusting Shafts

M

Mitch Newman

Member
I have removed the brake adjusting shafts from the front brakes on my 30 coupe. They appear to be in very good shape and very little wear. I was reading in Les Andrew's Mechanics Handbook that the length is not important, but that they match in length. My question is what is the allowable difference in length before you grind to adjust or buy new ones? I am sure there must be some allowable difference.
 
You also need to make sure the slot that fits on the shoe is tight to the shoe. The deepest point is the correct width but you need it thight to the shoe. If it is loose the shoe will have considerable in out play.

It is easy to fix. Sqeeze it in a vice.
 
Kevin;

I assume that you are referring to the hole at the top of the shoe where the adjusting shafts go in. What and where do you squeeze in a vice to correct this if the hole is too large?

Dick
 
I built a "length checker" to measure mine. It has a pivot for the shaft to pivot on and an adjustable, for length, angle. Adjust it for the shortest shaft then grind the others to fit. I use .003 as the margin of diference in length and the angle has to be the same also. The hole for the pivot has to have NO SLOP - thats the hard part. ken
 
Here is a tool that I copied from another member. It will allow you to accurately check the length of the Brake Adjusting Pins (A2042). Using this, you can then grind some pins,and make the lengths equal, and check to see if you ground the correct angle on them!
 

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On the pin opposite the wedge. The slot that you first slide the shoe into before you put the pin in hole.

When you put the pin on the shoe it should not rock back and forth.

Also keep in mind that the pins at both ends need to be tight in the holes of the shoes. They did not turn in the hole originally.

As for the length of the pin. I have have seen the prints, but Ford designed the shoes to thousands accuracy based on what I was told were on some prints. I have to think those pins need to be within a few thousands of each other if you expect even brake operation. Unless, you use a Barrett Brake Doktor. This tool sands the shoes to size on the axle and will equalize the differences of the pins.
 
"Unless, you use a Barrett Brake Doktor. This tool sands the shoes to size on the axle and will equalize the differences of the pins."

I would hope at the very least the Brake adjusting pin would be close to each other in length, or the Brake Doktor would/could sand all of the lining off one shoe, and barely touch the other one!
 
Thanks everyone for your information. First of all I did not realize that the "shoe slot" had to be tight. Now I do and I can check and correct if necessary. I measured mine utilizing a CMM where I work and both pairs have approx. .006" difference. Do you think that is too much? Just visually, they do not look very worn at all. Also, Jim thanks for the photo of the tool. Will have to build me one. What angle is the bevel? I guess I can measure it myself but thought you might know it off the top of your head.
 
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