Earthstar Forums

I'm on a quest to improve the crappy drum brakes that we all started with. I already have Hegar 6" wheels, and am looking at the Hegar disc brake package from Wicks Aircaft Supply. As most of these kits do, the Hegar kit supplies a solid keyed axle that has to replace the unkeyed hollow ones on the airplane. This means jacking the plane up on one side to allow removal of the axle. Has anyone done this, and do I have to build a wing support to hold the airplane up on that side? I'm nervous about putting a lift on the bottom of the fuselage for fear of breaking the fiberglass belly. Any ideas are helpfull.

kb

Hi, Kess. I jack up my J model using a tapered wood channel I made that fits underneath the gear leg and provides a level jack point. Then use a scissor jack or floor jack to lift it. I can send a picture if you want. Nothing fancy. I know you have gear leg fairings, so you would of course have to take them off to use this method.

I get real nervous about jacking up a wing to lift a wheel. I made a jacking mechanism for my RV that screws into the wing tiedown fitting and lifts the wing. It also attaches to the jack, so it "theoretically" cannot fall off and punch a hole in the wing. I chock the tires when I do this, but it still makes me nervous.

I think Mark had a suggestion to slip a half inch steel rod into the hollow axle and jack it up by that. That assumes you have a hollow axle (I don't,) and you'd have to take off the wheel pant. I guess you would most likely take the pant off anyway, otherwise why jack it up, right?

I jacked mine up with a small hydraulic floor jack placed at the crook of the
axle fitting. It was very easy and very secure with other wheel on the ground.
 Dick O'Reilly

Kess, the Hegar Brakes you are looking at: Are they the ones that have a small disc on the wheel, and a small full circle disc that presses against the inside face of the brake disc? I think the disc with the pad on it just rides in a housing with an O-ring around it, and the brake fluid is inside the housing?

If so, I tried a set of those many years ago on my N3 Pup. I was not impressed with their braking ability, and could not keep them bled, so I sent them back. I think the large O-ring around the pad disc was letting air into the system, though they did not seem to leak fluid.

They may have improved them since, or I may have just had a bad set, but both wheels had the same problem. I also felt that the small diameter disc just didn't give much braking force. I went back to the Go-Kart style drum brakes on the Pup, like you probably have on your Gull. They served me very well for 800 hours of operation on the Pup. It had 8:00 X 6 tires (larger than the Gull,) though the Pup was a bit lighter airplane. I hope they do as well on my Gull.

For those who are interested, I've attached some photos of my jack point. I had intended to clamp it to the fiberglass gear leg, but found it is not necessary. It fits snug on the leg, and with weight on it will not slip.







Riley

Also, I should mention that I jacked up my wheels to overhaul the drum brakes,
which needed nothing except new cables after 13 years and cleaning accumulated
gunk out of the mechanism. Mine work great and I really like their simplicity
and light weight.
 Dick O'Reilly

Hi Riley,
Thanks for responding right away. Yes I do have the hollow axles, and they are the ones that will have to be changed, so I won't be able to stick the 1/2" rod inside to jack up the wheel like I did when I installed wheel pants. All of these brake kits include a solid axle that is keyed to keep the caliper bracket from turning. If that backing plate could be fastened to the flange that we now use to support the drum brakes, things would be good. However, in most cases the whole axle must be removed and replaced with the new solid one. Therefore I will have to support the plane on one side without any load on the axle. I was proposing jacking the plane up with the rod inside existing axle, and letting the wing settle on a wing stand that will support it along the spar for 3 or 4 feet. Then switch sides if it works.

kb

Glad to hear that, Dick. I think one thing that greatly affects the effectiveness of the drum brakes is to see that the cables have smooth, gradual bends, and that the pedals are adjusted properly to give you a good push with your feet. I've seen some that had the heels set so far back that you couldn't get good pressure on them, and the angle was wrong.

Seems like a fine idea. In fact, if you had an extra person or two, maybe they could just lift the wing while you put the support under it.