9/13/18
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Following the advice of more experienced builders, I went with the Matco heavy duty "3 puck" brakes. These use a disk internal to the wheel, so one has to buy a package. (This is the brake and wheel combination pictured in the "Lucabration" builders log; the seller retained those wheels and brakes and delivered the aircraft on old Cleveland wheels and axles.)
Elsewhere I described the work of cutting open the existing gear leg fairing and installing a channel big enough for the brake lines I am using - stainless braid over a rubberized teflon inner core. Re building the gear legs to a nice airfoil took _way_ too long, and my shop is saturated with micro balloons. Now I need to construct the brake lines.
Side note on brake fluids... Past Cozy builders have had problems with overheated brakes, in one case resulting in a fire and loss of the aircraft, on another resulting in warped landing gear. A metal plate is commonly attached between the gear leg and brake, intended to protect the gear leg from brake heat. I will make this modification to the plans. I also intend to upgrade the brake fluid, moving from the standard mil spec 5606 to the current practice of a mil spec 83282 (Aeroshell 31, 51 or 61). Here is supporting text from an Aeroshell handbook (located here):
"Although the military did not move to phosphate ester type fluids they did identify the need for a more fire resistant fluid as a direct replacement for MIL-H-5606. As a result a synthetic hydrocarbon-based fluid, MIL-H-83282 was developed. This fluid is completely compatible with MIL-H-5606 fluids and MIL-H-5606 hydraulic system materials. All physical properties of MIL-H-83282 (now MIL-PRF-83282) were equivalent to or superior to those of MIL-H-5606 (now MIL-PRF-5606) except for low temperature viscosity. In particular all fire resistant properties of MIL-PRF-83282 are superior to those of MIL-PRF-5606. More recently MIL-PRF-87257 was introduced in order to address the concerns over the low temperature viscosity of MIL-PRF-83282."
2/12/18
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Over the past week I installed + reinstalled the axles, wheels and brakes. I ended up with a super slow leak to my new tubes - at $75 each that is a bit of bad news. And no, I did not pinch the tube between the wheel halves. I'll monitor it and might go back to Desser for a return and change over to the Michelin tubes.
I'm now waiting on ceramic insulation for the gear leg wrap, after which I can go final on the attachment of the wheels. Once the wheels are on for good I will move to the wheel pants. Fun to see wheel bearings clean of any grease - that's pretty rare! I like to use Mobile 1 bearing grease, so that's what you see loaded in the bearing packer.
I'll add spacer washers on each side of the aluminum heat shield, reducing the contact area and trying to isolate the gear leg from the heat that flows to the axle. And after I add the ceramic insulation I can fuss with the slight bend on the heat shield so that it best fits the installation.
And one more note - The aluminum axles were begging for an attachment point on the outside face. This can be used to secure the wheel pant, to hold a Wilhemson tip-back preventer, or pretty much anything else. A machine shop here in Tarpon Springs tapped the 4 AN3 holes in exchange for a plate of cookies.