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-   -   Brake centering tool (https://www.fordbarn.com/forum/showthread.php?t=89439)

jrapose 11-19-2012 03:41 PM

Brake centering tool
 

I have a question about using the brake centering tool.... is it needed just to set the brakes so the drums can be installed ? Once the drums are installed I thought the brakes would center themselves.

Or have I just been lucky installing shoes all these years ? Never used one of these tools...are they really needed.

Joel

ctlikon0712 11-19-2012 03:48 PM

Re: Brake centering tool
 

Unless you have a floater system, they don't center themselves. Everything that I have read say's that it is a very good idea. Required.....I dont know. I don't take any chances with brakes.
Good luck :)

Marco Tahtaras 11-19-2012 04:02 PM

Re: Brake centering tool
 

Even if you have the shoes arced to match the drum size, the odds of them being centered are remote. They will equalize on the rears but not on stock fronts.

It's important to note that there is more to a proper centering tool than most folks realize. The centering tool must be a micrometer of sorts OR have the ability to be sized to the drum that will be used. For example, if your drum is .043" over then the centering tool must be set to that size. If the centering tool is set too large or too small when setting up the shoes then they will no longer be centered when you properly adjust the adjusting wedge to match the drum.

If you go through this exercise correctly just one time I suspect you will be amazed what you find.

Will N 11-19-2012 04:10 PM

Re: Brake centering tool
 

Marco, Not sure I understand your point. If you center the shoes around the axle, and the drum braking surface is by design centered on the axle, how does it matter if the drum is oversized?

ericr 11-19-2012 07:01 PM

Re: Brake centering tool
 

Quote:

Originally Posted by Will N (Post 537228)
Marco, Not sure I understand your point. If you center the shoes around the axle, and the drum braking surface is by design centered on the axle, how does it matter if the drum is oversized?

my confusion is more fundamental than that....where exactly is there any adjustment provision within the front braking mechanism?

d.j. moordigian 11-19-2012 07:08 PM

Re: Brake centering tool
 

Borrowed this photo from *Afordman31*, thank you..This is a top view, the "wedge, with square head" is the adjustment. To the right side of the photo..

https://www.fordbarn.com/forum/attach...7&d=1352088259

BRENT in 10-uh-C 11-19-2012 07:32 PM

Re: Brake centering tool
 

Quote:

Originally Posted by d.j. moordigian (Post 537334)
Borrowed this photo from *Afordman31*, thank you..This is a top view, the "wedge, with square head" is the adjustment. To the right side of the photo..


Ohh jeez, ....the train has just "derailed"!! :D

ctlikon0712 11-19-2012 07:47 PM

Re: Brake centering tool
 

1 Attachment(s)
If your drums are turned to a larger diameter than the shoes, then they will contact in the center of the arc, not out towards the ends. This means you have a much smaller contact patch than you should. I.E. less brakes. Once the shoes have been ground to the proper dia. they need to be centered in the drum. Once centered then they can be adjusted in our out with the wedge. This only affects the drag or preset of the shoes before they are actuated. This is an exaggeration but think about it like this.... If you have a 14" rim in a 15" tire it’s only going to contact the tire's lip in one spot, not all across like it should. Even then the spot could be high or low and not on the centerline. Here is a pic someone posted here before that I borrowed. I have Barrett equipment, but this will get you by....
Good Luck

Tom Endy 11-19-2012 08:00 PM

Re: Brake centering tool
 

If you install Flat Head Ted's floater kit the front brakes will then automatically center. The rear brakes only half center. In addition to Flathead's floaters installed in the rear adjusters, he also provides what he calls "pins" that replace the rollers that slide on the roller tracks. For each rear wheel the pins are a pair that are a mirror image to each other. Instead of a roller there is a four sided eccentric with a 1\16" difference to each side. By selecting a given side you center the other half. You need a centering tool to accomplish this. Bratton sells one that will do the job. Page 156 in their catalog, part number 2695, $44.00.

According to some literature I have seen the centering of the original rear brakes is supposed to be accomplished by bending the roller tracks up or down.

Tom Endy

Bob C 11-19-2012 08:06 PM

Re: Brake centering tool
 

1 Attachment(s)
This is the one I use.

Bob

jkeesey 11-19-2012 08:11 PM

Re: Brake centering tool
 

You center the front by bending the flats of the roller track up or down.

Kevin in NJ 11-19-2012 09:07 PM

Re: Brake centering tool
 

Brake shoe sizer and centering tool

This tool can be set to the radius of the drum and then used to check the shoes on the wheel and center them too. The $99 this guy is asking is too much money for it but it is a solution.

The best tool for the A is the Barret Brake Doktor. This attaches to the axle and sands the shoes to size on the car. This means the shoes will also be centered to the axle.

jkeesey 11-19-2012 09:12 PM

Re: Brake centering tool
 

Kevin the only problem I see with the brake doctor is if it sands the shoes to fit the drums its not really centering them. It would cause one shoe to wear out before the other.

Kevin in NJ 11-19-2012 09:43 PM

Re: Brake centering tool
 

The tool is attached to the axle with the shoes mounted. You then turn the tool around as the disk sander sands the shoes to diameter. The shoes have to be centered as it is swinging around the axle.

The differential thickness is not much unless you put some way off hardware on the shoes. Besides, how many drive their car enough to wear out the shoes? Most cars are not driven enough to wear the brakes to the drums in less then a few years. This makes getting the center and diameter of the shoe even more important from the start. Otherwise you may take years to get full braking as the shoes wear to fit the drums.

It is a royal pain in the butt to make all the brake parts give you a centered fit to the accuracy you get with the Doktor tool. Short of getting all NOS brake parts the best brakes will come from properly using the Doktor.

700rpm 11-19-2012 09:57 PM

Re: Brake centering tool
 

But if the shoes are arced to fit the drums, then centered with a centering tool, doesn't that take care of the possible oversized drum problem?

Bob C 11-19-2012 10:12 PM

Re: Brake centering tool
 

1 Attachment(s)
This is the shoe grinder.

Bob

jrapose 11-19-2012 11:14 PM

Re: Brake centering tool
 

I am going to copy Craig's econo-tools he made and give it a try.....now that it has been explained I think I understand........all these years I have always had hydraulics and did not experience the fun of mechanical brakes....and all the little tricks to them....ie. that darn emergiency brake return coil spring nightmare.

Thanks Guys
Joel Rapose
Chester Ca,

ctlikon0712 11-19-2012 11:22 PM

Re: Brake centering tool
 

700rpm, "yes" is the answer.

jrapose 11-19-2012 11:45 PM

Re: Brake centering tool
 

Yes, I agree now, I just put the drums on and they bearly turn...I think I can make a tool quickly now that I see what it needs to do.

Thanks again
Joel

Marco Tahtaras 11-20-2012 12:03 AM

Re: Brake centering tool
 

Quote:

Originally Posted by ctlikon0712 (Post 537516)
700rpm, "yes" is the answer.

Not exactly. First, the most common way to "arc" the shoes is by grinding them with an artificial center. The shoes get thin spots like other grinding methods MAY do so no gain AT BEST on the wear factor.

Second, over the decades many shops have altered the radius of the steel shoe by peening the web. These will not easily grind to your proper arc AND you have now changed the length of the shoe between it's two anchor/alignment points. Also it means it will have to push outward at a different rate than it's counterpart unless they're an exact match.


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