Author Topic: replacement brake shoes  (Read 14624 times)

Ricks

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Re: replacement brake shoes
« Reply #15 on: August 18, 2014, 01:09:38 PM »
Rick

kartjockey

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Re: replacement brake shoes
« Reply #16 on: August 18, 2014, 01:37:41 PM »
The one you just linked to is only 5/32 thick and mine are 3/16. That would be another 1/16 inch smaller than drum diameter

Ricks

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Re: replacement brake shoes
« Reply #17 on: August 18, 2014, 01:45:03 PM »
Is that the wire we see on the inside diameter?
Rick

Gramps

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Re: replacement brake shoes
« Reply #18 on: August 18, 2014, 03:13:17 PM »
As you can see in these two pictures the band brake would be on the outside of the drum. In my way of thinking the wire would be there to hold the material together and/or for bonding to the band. If the wire was on the friction side and wore off the lining would lose its structural integrity.
Anytime you have a 50-50 chance of getting something right,
There's a 90% probability you'll get it wrong.

Ricks

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Re: replacement brake shoes
« Reply #19 on: August 18, 2014, 03:17:41 PM »
Gramps, I agree with you.  Look at the pictures Tom posted.  To me, it looks like the wire is on the inside of the radius, which looks to be the non friction side.  If this is used on a band brake, it looks like it would rub on the wire, but in our brakes, would work as designed.
Rick

Gramps

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Re: replacement brake shoes
« Reply #20 on: August 18, 2014, 03:32:23 PM »
Anytime you have a 50-50 chance of getting something right,
There's a 90% probability you'll get it wrong.

Ricks

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Rick

kartjockey

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Re: replacement brake shoes
« Reply #22 on: August 18, 2014, 03:48:41 PM »
oh the paralysis of analysis!  LoL.  the wire on this is miniscule.  one strand measure .009 of an inch. probably the perfect amount of added strength

kartjockey

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Re: replacement brake shoes
« Reply #23 on: August 18, 2014, 03:54:48 PM »
I like that clutch bell brake.  Never thought of that one!

lamptester55

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Re: replacement brake shoes
« Reply #24 on: August 19, 2014, 11:32:13 AM »
In my former life I tested automotive brakes, so I got thinking about the relining problem. I have reservations about using the flexible lining with rivets. You might consider this. JB Weld epoxy is available in automotive stores. It can withstand high temperatures from engine blocks and will hold torque when used to rethread a stripped hole.

Clean the surface of the brake shoes. Install the brake shoes on the brake backing plate. Slip a piece of wax paper between the shoes and the backing plate to keep the shoes from being bonded to the backing plate. Obtain two good hose clamps sufficient in diameter to surround the brake shoes. Cut the brake lining to the required length, apply a minimal amount of epoxy to the surface of the brake lining (enough to squeeze out a bit , but not too much). Slip a hose clamp around the brake shoes with enough room to slip in the brake linings. Position the brake linings and tighten the clamp. Check the position of the linings and re-adjust if necessary. After the first clamp has been tightened, install the second clamp to give full pressure on the complete surface of the brake linings. Wait 24 hours, remove clamps and clean off excess epoxy and trim the brake linings at the edges if necessary.

If the diameter of the linings is too large to install, use a strip of emery cloth or sandpaper in the old shoe shining method and reduce the thickness of the linings equally on each shoe until the desired fit is accomplished.  

There is probably no way to determine the longevity of the lining, so it is advisable to check the shoes on a regular basis.
« Last Edit: August 19, 2014, 02:50:19 PM by lamptester55 »

Ricks

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Re: replacement brake shoes
« Reply #25 on: August 19, 2014, 11:55:46 AM »
Would you recommend riveting after the JB weld sets up?
Rick

lamptester55

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Re: replacement brake shoes
« Reply #26 on: August 20, 2014, 04:22:25 PM »
I don't see any need for the rivets. JB Weld creates a tremendously strong bond.  Doing a <<<good job>>> of counter boring the brake linings to install rivets requires a special drill such as one used for counter boring holes for Allen cap screws.

JB Weld a couple pieces of metal together, then try to get them apart.

My cousin who is a machinist put me on to JB Weld about 20 years back. I have been using it ever since. I just fixed the starter switch in my compressor motor a couple weeks back using JB Weld. No repair part available, $500 for a new motor.

kartjockey

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Re: replacement brake shoes
« Reply #27 on: September 10, 2014, 05:37:24 PM »
So here is a picture of my lining fixture.  I can put it in the mill and program the drill positions to make each lining have the correct hole pattern to fit the shoe. Once I have told the computer were the starting point is the fixture will repeat the hole pattern by installing the lining into the corner each time. I have found the linings to be the same either front or rear and top and bottom,  however, there is an inside and outside as one side of the rivets is closer to the edge of the shoe then the other. These shoes require a #4/4 rivet.  This is 9/64 in diameter, 5/16 flathead that is 1/4 of an inch long. You must counter bore the lining to a depth of .125 leaving .062. Mike Sal is correct when he said you must grind clearance in the side of the riveting tool as the rivets are very close to the center web of the shoe.

I also have a plan to start with a thicker lining material, rivet it in place,  and then make another fixture resembling that of the backing plate, install the shoes on it just as you would on the wheel.  Then put this fixture in my lathe and arc the shoes to match the diameter of the drum.(use to do this years ago on car linings) This will provide complete usage of the length of the lining and will also allow the cam to work as close to its pivot providing as much leverage as the cam can give.   I noticed on the brakes that I have that the cam was working towards the outer edge. Along with all of this I have dusted the actuator end of the shoes just enough to square and true them up so that they are smooth again with no wear marks.

Anyone wanting to try my brake shoes can contact me and we will talk.  Biggest thing is I don't have any cores to pre-make any shoes ahead so I would need to do your shoes. 

relic

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Re: replacement brake shoes
« Reply #28 on: September 10, 2014, 08:08:35 PM »
kartjockey i want your mill!! lol! i sold mine a few years back-ugh!
The bitterness of poor quality, lingers long after the sweetness of low cost!

kartjockey

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Re: replacement brake shoes
« Reply #29 on: September 30, 2014, 04:53:53 PM »
Since the brake linings are flying off the self I thought I would make some more!