O-ring material for DOT-3 fluid

On Wednesday, January 7, 2015 8:45:53 AM UTC-8, Dave Nadler wrote:

Thanks Bumper!
Was there a change to the cylinder liner as well as the pistons?
If one finds an early corroded unit, what to do?
Just hone the cylinder?
Replace un-annodized pistons with new parts from Cleveland?
Thanks again for the education,
Best Regards, Dave

Not sure if Cleveland anodized the calipers, but I don't think so. The Corvette guys have been rebuilding the older car calipers due to corrosion with plain aluminum calipers. There's a cottage industry boring out the cylinders, then epoxying in a brass liner, which solves the problem completely. A company called Sierra Brass did the ones for my previous Stemme, around $70 a 14 years ago, I doubt they are still in business as the guy was getting up there (kinda like me now :c) and I couldn't find him w/ a quick search.

I anodized the pucks myself, as I have a small set up for making little aluminum parts pretty. Any anodize/plating shop should be able to do it for a few bucks.

This link will give you some leads on resleeving cylinders: http://forums.aaca.org/f120/resleevi...er-341332.html

bumper

I also anodized my Cleveland 30-9 brake caliper.
With mixed success.
See my project at
https://sites.google.com/site/threeu...-brake/caliper

Bumper, I think the guy you are referring to is Joe or Jack Way at Sierra Specialty Automotive in Quincy, Ca.
http://www.brakecylinder.com/contact.htm
indeed, he retired, as the webpage says.

I was in touch with him 3 years ago for a brass sleeve job on my caliper, but he indicated that he had stopped doing aviation stuff for liability reasons.
If I recall well, he had some sleeves pushed out.
(Learning: tell your shop it is for a cart or something like that)

My anodizing job (done at a local shop) was not as successful as I had hoped for. I think the problem was in the severe pitting.
The anodizing does not fill in the pitting.
As is visible in the images, both the caliper and the piston were pitted where the O-ring sits.
I tried to polish that out, but could not get in deep enough.
Now, in very hot weather (100 F) the caliper leaks a bit.
I thinks the DOT4 gets so thin that it creeps through the pitting past the O-ring.

My suggestion: If you are looking to anodize your brake system and your aluminum is corroded, take care of the pitting first before you do the anodizing.

3U

On Thursday, January 8, 2015 at 12:52:00 PM UTC-8, wrote:
I also anodized my Cleveland 30-9 brake caliper.
With mixed success.
See my project at
https://sites.google.com/site/threeu...-brake/caliper


3U,

Nice work!

For the pucks, simple to make new ones on a lathe.

I know one gentleman who filled the caliper bore pits with JB Weld, then sanded smooth. It worked, at least initially. I moved from that airport so don't know long term efficacy - I imagine little bits of JB Weld would come loose and fowl the works.

bumper