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#1536373
I've thrown in the towel with my Cleveland brakes.

Unfortunately, the prohibitive cost of new caliper/piston assemblies both sides means looking for an alternative manufacturer. My Stinson is on a Permit and I've already tried some secondhand ones without success.

Looking at Matco prices in LAS Aero's catalogue they look very good especially as it includes wheels, disc rotors, back plates and brakes complete.

Problem is I'm having trouble specifying what I need. The only 6" wheel/brake combo on a 1.5" axle has an internal caliper and the backplate bolt pattern is different. Just to complicate matters mine has a welded backplate and the axle isn't a square ended 4 bolt attachment.

If anybody has experience of this revision and can help I'll be forever grateful.

Many thanks.
#1536378
Looks like cost differential is around £700 (for 2no Cleveland calipers/vs pair of Matco wheel/brake units complete) which I agree is a lot but, from experience of other LAA owners doing brake mods, I would suggest that you take care that the cost and faff of making a modification to enable fitting of the cheaper units does not exceed the value of ease (+speed?) of like for like replacement of existing type of brake parts.

As a matter of interest, What is wrong with your old units that prohibits refurbishment of those?
#1536396
In the Automotive world, there are specialists who can bore-out, and stainless-steel sleeve a caliper and supply new stainless pistons.
the bore of a caliper is not critical, it's purely a mechanical guide for the piston The outer-face and base of the seal-groove are the critical faces on which the seal-ring presses. Likewise, the piston-surface which projects beyond (outboard) of the seal, when the piston is fully retracted,is unimportant. The outer bellows is just a dirt and dust seal. there is a lot of bunkum talked about brakes, scaremongering promotes sales!

I'd be amazed if your calipers were not reclaimable at a fraction of new cost (provided there are service-kits available.)
#1536405
Steve,
Cleveland brakes of the type I think we are discussing here are very simple units, with calliper casting parent bored for the sealing face (single O ring). There are no bellows nor any other dirt protection - this coupled with the tiny amount of movement in normal service on aircraft brake systems is why they tend to corrode and seize.

Incidentally, DOT4 fluids are in use in Cleveland systems on some more modern gliders, so fluid type should not cause a problem with the metal surface corrosion. However, incorrect fluid/O ring combination will always end in tears.
I carry in stock O rings for mineral and synthetic fluids and fit as required by a/c maintenance Manual.
#1536434
Incidentally, DOT4 fluids are in use in Cleveland systems on some more modern gliders, so fluid type should not cause a problem with the metal surface corrosion. However, incorrect fluid/O ring combination will always end in tears.
ha!- tell me about it! Early Rolls Shadow used Dot 3, AKA RR363 Brakes and suspension were fed by it and there was a complex 2-speed levelling, which switched to "rapid" when a door was opened........all that highly hygroscopic fluid rotting the amazingly complex ststem from the inside! Sanity eventually prevailed, the 2-speed went, as did the front levelling and it all went over to LHM , the same as Citroens, from whom the brakes/ suspension were licensed.

A mistake costs THOUSANDS to rectify...Some David Brown tractors and Huddersfield-built Launderette spin-dryers also used LHM in the brakes As It's very close to Auto- transmission fluid (which Citroen approve for emergency use ) and it doesn't boil/ vapour -lock, lubricates and protects internal surfaces, ...Mr Cynic here is convinced that huge vested interests promote the continued use of Dot4. (Dot 5 is a totally different beast, it is NOT "better" for road vehicles (use for competition and track-use only)

The Cleveland setup sounds like the typical Aviation "certified" engineering rip-offs I keep reading about.

As the OP is running a Permit machine, he could probably get the LAA to approve a mod.

Hard-chrome the bores and pistons..../ modify the mouth of the bore to accept a standard bellows-type dirt-seal, but most importantly, smear a good coating of brake-rubber grease on the piston and cylinder, prior to assembly....this should ensure the exposed gap is filled with rubber-grease instead of moisture and crud. Where pads seat in caliper-slots, it's worth using a file/scraper to remove all corrosion build-up
on the pressure- bearing areas and coat with the merest smear of copper-grease. Attention to the details can transform a poor braking- system. (I earned my spurs on Fiats and their alloy sliding calipers, that didn't slide in most cases :lol: )
#1536540
Thanks U72, I'm coming round to this course of action. It will certainly see me and CloudHound back int'air quickest.

Most of the kit is serviceable so it's the main body of the brake unit plus the piston and O rings I need. I've also decided to replace the brake lines, remote reservoir and fittings (in brass this time) so that seems to be route one to goal.
#1536565
CH,
I have just remembered that I have a pair of Cleveland brake units in my stores that are surplus to requirements. They are as supplied, in original boxes, still with release paperwork. They were bought for a job ten or more years ago but never fitted and have migrated to the back of the cabinet where they have been resting undisturbed since.

If of any interest, PM the part numbers you are looking for and I shall check if these might do your job.