This is a fairly big job. Once I got the brakes upgraded, I need to get the wheels and brakes mounted to the gear legs. The first challenge is that the gear leg needs to be cut.
Here’s the bottom of the gear leg and the four holes that are used to bolt the axle and brake torque plate to the gear leg.
This is the gear leg side of the axle mounting flange.
Notice where the caliper is? Well not only does the gear leg have to be cut, it’s going to be cut REALLY close to those bottom holes. So the first thing that I need to figure out EXACTLY where to make that cut. I don’t want it any shorter than possible. To determine the cut location, I made a template from some masonite. It was basically trial and error but eventually I ended up with this.
Because black ink won’t show up on the gear leg, I applied some masking tape.
Then position the template with the four bolts.
And trace.
The next challenge was to make the cut. If the gear leg was made out of wood, I’d leave the template on and use a router. But the material used in the gear leg is TOUGH. So that’s out of the question. I would probably ruin two $25 bandsaw blades cutting the two gear legs. Malcolm at Hangar 18 suggested using Permagrit blades in a jjigsaw. About $3 for a blade and it went through the gear leg like butter.
The heat generated by the brakes could cause the gear leg to weaken over time. To prevent this a heat shield is used. The factory ships a “phelolic” sheet with the kit that is placed between the gear leg and the axle/brake/wheel assembly. I elected to upgrade to a material called “Garolite”. This has much better heat shielding properties. It’s pricey (about $50 for a sheet) and the minimum size is enough to make four shields. But after I made mine, I sold the remaining stock to another builder so it only cost $25 for both gear legs. In aviation money, that’s a bargain!
To cut the material, I used my template again. First I clamped to the Garolite to the template and marked it.
Then I cut the Garolite with the jigsaw and cleaned it up with a carbide burr.
To allow movement of the brake caliper through it’s entire range, I had to create a notch for the upper torque plate mounting bolt.
Once I mounted everything, I had to disassemble everything and grind off material from the gear leg here and there until all the parts had necessary clearance. I probably mounted and removed the brakes over a dozen times.
Here’s the end result.
