STC for cheaper brake discs

[LakeheadFlyer]

Just wondering if there's any interest in an STC for using the newer 1 piece brake disc (164-01900) instead of the riveted 2 piece style (159-00100). The main reason for this would be because your Comanche is registered in Canada (like mine), where there is no 337 form, or simple way of using the cheaper disc (legally). The best we can do is an STC for a specific serialized aircraft (or so says my DAR). Now he also mentioned that the serialized STC is about the same amount of work as an STC, which got me thinking. If there were other people interested in pooling in on the costs of a formal STC, then it may be worth it, depending on how often you have your brakes changed. For myself it's not worth it at all, even with buying used 40-84 and 30-41B's.

The cost of the Serialized STC would be about $1K. I will check to see if it's around the same price for the STC today.

Let me know if there's any interest out there. I could always pay for the STC to be completed and sell it too (for a fair price to recoup the costs of creating the STC).

I'm really not thinking this is going to go anywhere because of the costs involved and the frequency of brake changes, but thought I'd check anyways.

[DAVEG24]

Not trying to steal your idea, but how would you actually go about doing this? With talks that I have had with Cleveland in the past, they have offered part numbers for new wheels, brake discs, and brake calipers that would be legal and facilitate the ability to change out brake discs when needed without having to rivet them in place. The cost is hardly worth it. On the other hand, the only way I know of to put a bolt on disc on a wheel designed for a rivet on disc, is to machine off the collar (ridge) stop in the wheel, which I doubt would ever get approval. You may have some other idea which may work. If so, I'd be interested.

Dave Gitelman

[LakeheadFlyer]

I did talk to Cleveland about 1 month ago about this. The tech representative that I spoke with told me that the new wheel assembly and brake assembly, though would fit and work, wouldn't be a legal replacement. This is simply due to the applicability of the parts to the serialized aircraft. See the attachment.



I actually have not spoken with Transport Canada about this. I'm going off the direction of my DAR who has looked at a form 337 of one done. Perhaps I will contact my Transport Canada Rep to see what his thoughts are.

Absolutely the best way is to directly replace the old parts with the new parts. Machining the wheel would be far more complicated I'm sure, since the integrity of the engineered part would be altered.

I can't remember exactly, but the cost of the whole new set up for both wheels and brakes from Webco was under $2000 ( I think $1850 or so). You can also find them used for much less. New bolt on brakes and pads are $165 per wheel, so $330 for both. The cost of new rivet on discs and pads are around $500 per wheel, so $1000 for both. If you end up changing the discs twice, then it will just about be worth it (excluding the STC cost, or 337 if you live in the U.S.). If the SCT cost $1000 to get, then sell the STC for $100 ten times and it's worth it. Change the discs three times and it's a no-brainer (with the cost of the STC reduced).

How often do you change discs? This is the first time for me. Again I still don't think it's worth it, unless there was a large response of people interested in going this route.

[DAVEG24]

Interesting. When I spoke with Cleveland, 10 or more years ago, what they offered was a lot more expensive, and legal. I've owned my Comanche for 43 years and have changed the discs about 4 or 5 times. They used to be reasonably priced so it wasn't a big deal. Now they are outrageously priced. I have a new set sitting on the shelf, so when I need to replace, I'm all set. I don't think I could ever be convinced to spend $500 for one brake disc. Good luck. I'll be interested in what you come up with.

Dave Gitelman

[LakeheadFlyer]

Never mind. The Transport Canada fee for an STC is much more than a serialized STC. It will cost closer to $2500 to get this done, and there doesn't seem to be enough interest to make it financially viable. I guess I'm spending $1000 on new brakes (yikes!).

[Rick Greer]

I am a new Comanche owner, I bought mine from a "buddy" of mine. He then talked me into replacing the brakes and the stainless brake caliper, with his help. Calipers, that 's what I've always called them. We rivetted new pads on too. That all went okay. However, drilling out the rivets AND seperating the wheel assembly from the old caliper was a nightmare. Nearly 2 1/2 hours later we ended up chiseling them apart which acctually worked well. I'm a little concerned though. Did I do something wrong? Am I legal? You thoughts?

[Zach Grant L1011jock]

Calipers are the part of the brake that has the piston actuators and the brake line attached to it. Pads or linings are attached to the pressure plates, and those pads act as friction surfaces against the disk, which is attached to the wheel, either by rivets in the case of the older models, or are bolted to the wheel with using the same through bolts that hold the wheel halves together in the case of the newer wheels. I include this terminology, because I am a bit confused by your post, and chisleing the caliper apart would certainly render it unusable.
-Zach

[MULEFLY]

I've tried the cheaper brakes calipers and pads... Rapco, black ones, etc. Clevelands are the best value...

JMHO
Jim

[Rick Greer]

Well, since I don't know the part names, let's just say, we chiseled the rivoted pressure plate from the half wheel hub. Then we replaced the rivoted pressure plate with a stainless one that bolts through the half wheel hub. How am I doing? No I didn't chisel the calipers. Some cleaning up of the wheel hub was necessary just to remove a slight ridge from 50 plus years.

[Ray B]

I think your confusing the presser plate and the brake disc. If you have a Spruce & Specialty catalog available you can look up an exploded view picture of the assembly for a clearer understanding. Ray B

[SLIMDREDGER]

Mulefly:

I couldn't agree with you more on replacing with Cleveland discs! To the best of my memory, I had not replaced the discs in the 45 years I owned the airplane, and from somewhere I had the idea that Cleveland didn't make the originals that I had.

At the annual we replaced with " Black Steel" and I broke them in per instructions. Braking action was never as good as the original set up. At the next annual we polished the discs and put in new friction surfaces and again followed the break in instructions to the letter. Braking action is better, but still not equal to the original set up, in my sense.

Regards, Al Powers ICS 2978