Azusa Brake Setup: Removing the Springs

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Azusa Brake Setup: Removing the Springs

Postby Don_P » Fri Aug 01, 2014 1:43 am

The Sonex instruction for installing the Azusa mechanical brakes calls for rounding the edges of the brake-shoe cam so that the cam will turn smoother. Trouble is, you've got to remove the cam to do this, and that means the springs have to come out. I've busted half my knuckles trying to do that, and automotive spring removal pliers are pretty much useless since the springs are not anchored to studs. Would love to hear from anyone who has been able to solve this problem.
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Re: Azusa Brake Setup: Removing the Springs

Postby hsjvorster » Fri Aug 01, 2014 8:25 am

Take two hefty screwdrivers, cross them over the pivot point on the opposite of the cam, the points of the screwdrivers on the inside of the brake shoes. Press the screwdrivers at the back(?) towards each other to extend the springs and open the brake shoes. If somebody could just help you to remove the cam.

Hope I am clear
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Re: Azusa Brake Setup: Removing the Springs

Postby gammaxy » Fri Aug 01, 2014 10:30 am

I used pliers to bend one of the hooks on the end of the spring just far enough to make it easy to stretch the spring and pull it out--probably 45 degrees or so, maybe less (the less the better). I squeezed it back after re-installing it.

This made the job almost too easy with little possibility of busted knuckles.

At the time, I didn't really think about the possibility of work hardening the spring, but it didn't seem like I bent it far or sharp enough to be a problem. If I were to do it again, I'd probably do it to the spring at the pivot point that doesn't get stretched as much.
Chris Madsen
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Re: Azusa Brake Setup: Removing the Springs

Postby Gripdana » Fri Aug 01, 2014 3:47 pm

I used a large pair of snap ring pliers that open when squeezed.
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Re: Azusa Brake Setup: Removing the Springs

Postby hickej » Sat Aug 02, 2014 10:15 am

This can be done with no tools when the brakes are on the axle. Put on a pair of gloves and pull one brake pad away from the center until you can 'tip' it away from the backing plate. I need two hands to do it. Putting it back on uses the leverage from the tip to stretch the springs.
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Re: Azusa Brake Setup: Removing the Springs

Postby Don_P » Sun Aug 17, 2014 9:42 pm

Thanks for everyone's advice. I finally got in touch with Kerry Fores on this. He said to just fold the shoes together like butterfly wings. This worked surprisingly well. When folding them, if they get stuck halfway, hold them in place with one hand and pry gently at the point where the tops of the shoes rest on the cam. That will get them going again. Putting them back on is just as easy. Start with the shoes in the folded position, set them in place with the top of the shoes on either side of the cam and the bottoms on either side of the pivot point, then press them flat. Be sure to wear heavy gloves and safety glasses unless you like smashed fingers or black eyes.
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