Wednesday, October 21, 2015

Brake Lines - Rear Seat Backs

Productive night tonight! Now that the parking brake valve mount has been made, we can start with actually fabricating the brake lines. There are a total of four brake lines to make: One under each front seat going from the landing gear mount to the tunnel (where the parking brake valve is), and then one on each side of the tunnel going forward from the valve and up the firewall, terminating at a bracket on the upper left area of the firewall. I'll be making these runs out of 5052-O aluminum tubing, which is a stronger material than the provided 3003 alloy in the kit (3003 is not used on brake lines in production aircraft). This is a common upgrade that I decided to go for and had previously ordered the necessary lengths from Aircraft Spruce.

Meanwhile, Sarah came out and first helped rivet the parking brake valve brackets to the bottom fuse skin in the tunnel, and then decided to start working on the rear seats (Section 42). We're going to try a small modification here and make the back seat more of a 60/40 bench-style seat as opposed to individual buckets. Cleaveland sells a kit to do something similar (with headrests and all), but we're going to try to keep it simpler and just extend the left-side seatback using an extra F-637A seatback panel which I added to my finish kit order. So in the meantime, Sarah can still make many of the supporting bits needed to assemble the seats. No pics yet of these parts, but she made a number of parts out of aluminum angle to form the structure of the seat backs.

Back in Section 36, I got started on bending brake lines. The first ones to make are the ones that go under the front seats. They are relatively straightforward, and I began using a technique I read about on the forums, where you take a piece of solid-core copper house wire and bend it to the desired length and shape, and then use that as a template to make the actual brake line.

Copper wire cut and formed to desired shape for brake line

Using the wire as a template, I got out the 1/4" 5052 tubing and used my OTC 6515 tubing bender to make the same part out of brake line:

5052 tubing bent to shape from wire template

In this way, I made both brake lines that go under the seats, and decided that was enough for tonight. It turns out Sarah finished making her brackets but didn't feel like busting out the drill, and I had finished my two brake lines but didn't feel like busting out the flaring tool. Still a very productive evening, and with a few more nights like this we might have two more sections crossed off the to-do list!