Cadet Brakes

[Bill Poynter]

What kind of experiences have you had with your Cadet's brakes?

[Brett Lovett]

I have the expander tube brakes, but the original master cylinders have been replaced.  I can't remember the brand of the new ones, but they are large, vertically mounted cylinders.

[Woody]

Go to the accident reports of the Culver and there is a couple of accidents directly related to the expander brakes.  Because of this and the fact that this plane is out of production, I chose Grove wheels and brakes which is acceptable.

[Brett Lovett]

I read through all the NTSB accident reports for the Culver Cadets and found only one accident report related to expander tube brakes, and the pilot in the report calls them "Goodyear 'expanded tube' brakes".   I question his "known to lock up if overheated" statement, as I've never heard that from any other source.  The only other report I can find that relates to a brake failure cites a "broken rotor disk" so obviously not expander tubes.

I also have Hayes/Goodrich expander tube brakes on my Piper Vagabond, and I'm entirely satisfied with their operation.

The best reason for abandoning the expander tube brakes is the cost and scarcity of replacement parts, particularly if you do not have tailwheel steering.  I believe the Grove brakes are the best replacement option as they are designed for use with existing 4 inch wheels and are a direct replacement for the expander tube brakes, however they are not STC'ed for use on Culver Aircraft. 

[Bill Poynter]

It’s my opinion that the Cleveland 5” wheels and brakes are the most practical solution for the Cadet.  They are FAA PMA approved and there lots of Cadets with previously approved installations.  The outside diameter of the 5.00-5 tire is very close to the O.D. of the 5.00-4 original tire, so fitting into the wheel well is not a big issue.  The 5.00-5 tires and tubes are readily available at reasonable prices from several manufacturers.  The only company making the 5.00-4 tire that I’m aware of is Goodyear.  The current Aircraft Spruce price on a pair of 5.00-4 tires and tubes is $731.80 plus freight.  That difference in tire and tube price would go a long way toward justifying the cost of converting to Cleveland.

[Brett Lovett]

Desser has the Goodyear 5.00-4 6 ply tires new at $263.00 each and retread at $165.00 each.  I believe the correct tubes are $75.67 each.  Desser carries Aero Classic tubes which I found to be better quality than the original Goodyear tubes.  I originally purchased Goodyear tubes for mine and found they were leaking through several pinholes in the area where the valve stem was vulcanized to the tube.  I had them replaced by Aero Classic tubes which worked fine.

[Bill Poynter]

If anyone is interested in converting their wheels and brakes to Clevelands, here's everything it would take including the tires, up for auction on eBay: http://www.ebay.com/itm/Wheels-Brakes-Axles-Tires-and-Tubes-Cleveland-Kit-199-102-Homebilt-/190624669946?pt=Motors_Aviation_Parts_Gear&vxp=mtr&hash=item2c621da0fa

The only other things you would need are master cylinders.

[JoeB]

If anyone is interested in converting their wheels and brakes to Clevelands, here's everything it would take including the tires, up for auction on eBay: http://www.ebay.com/itm/Wheels-Brakes-Axles-Tires-and-Tubes-Cleveland-Kit-199-102-Homebilt-/190624669946?pt=Motors_Aviation_Parts_Gear&vxp=mtr&hash=item2c621da0fa

The only other things you would need are master cylinders.

hmm, that's interesting - I'm going to keep an eye on this auction. 

I found the 337 and master cyl details on your website Bill, thanks for sharing this info!

[Bill Poynter]

There are 337's covering several different models of master cylinders.  The one I chose was the Cleveland 10-30.  It has a bore of .552".  The pedal geometry on a Cadet makes my brakes a little touchy with more pedal travel than I would prefer.  A larger bore would solve both of those issues.  There's a 337 utilizing the model 10-20 which has a bore of .563.  I think that's what I'll use on my current project.  In order for the them to fit in the place where the old cylinders were mounted, you'll need to pick cylinders with the ports aligned at 90 degrees to the pivot hole on the end.

Since these master cylinders pivot slightly when applying the brakes, I used a flexible brake line all the way to the cylinders. 

I recommend mounting a reservoir out on the firewall.  This really simplifies servicing the brake fluid.  Doing it upside-down under the panel is really difficult.  The brakes should be bled by pumping 5606 into the nipples on the calipers.  Another important thing in bleeding the brakes is to elevate the tail high enough so that all air bubbles are forced out the inlet port of the master cylinders.  If you leave the tail on the ground while bleeding the brakes, you're sure to trap air in the master cylinders.

There are a couple of 337's that state that they reused the original master cylinders.  If you elect to do that, consider what type of brake fluid you will use.  The original brakes used automotive brake fluid. The Clevelands use 5605 hydraulic fluid.  The original automotive brake master cylinders aren't compatible with 5606.  Dot 5 fluid is a possibility, but I think the FAA would be happier with a solution that utilized 5606. 

[JoeB]

I'm collecting parts and I don't even have the airplane home yet!  Wheels and brakes arrived in the mail today.
Thanks for the heads up on that auction, the parts are in great shape and I think I got a pretty nice deal.
-Joe

[Neal LaFrance]

The easy solution to wheels and brakes for the Cadet is to Contact Roby Grove at  ------------------- www.groveaircraft.com. He has a 500x5 magneesuim wheals. Changeing out my wheals and brakes on my cadet. Weighed the 500x4 with tire aganst the 500X5 13 lbs, the same. The heavery the wheal the harder it is to rertract. Neal

[Scott Crosby]

Wouldn't Grove's Cub 8:00x4:00 disc brake conversion work for somebody who already had good original Hayes/Goodrich 5.00X4.00 wheels and tires?  I think the disc would rivit on just the same as on the Cub's wider wheels. And, there would be no clearance/weight issues using the original wheels.

[Scott Crosby]

Whoops...Brett already mentioned the Grove Cub 4" conversion above.

On a different note - anybody know what the source for the original master cylinders is?  I think it is early Plymouth but could be wrong.

Thanks,
Scott

[Paul Rule]

My "Culvers Going Places" (Issue #5) says the original master cylinders are from a 1939 Plymoth.

[Neal LaFrance]

Hi This Is Neal again. Wheel and brakes for the Cadet STF and the Culver Cadet. I have the Shin wheel modified with disk brakes ,they have worked ok for the past years, how ever you will brake the bank buying tires and tubes for this wheel 500 X 4. The Cadet STF has been up for service on the landing gear, so have decide to go to the 500 X 5 wheel. My friend Roby Grove Has his Grove Aviation business three hangars east of our hangar, so I bought the weels and brakes from him. Here is my reason. Roby has magneisum wheels. I weighed the Shin wheel assembly with tire, aganst Rody's wheel same weight. The effort to
retract the gear will be the same and ditto for the G loads.