Section 36 Brake Lines

Section 36 Brake Lines

: NOTE: This page describes the installation of the left Brake System Between the Tunnel and Brake Line exit Location on the left side of the aircraft. Repeat the steps on this page for the right side of the aircraft. The right installation is a mirror of the left.

Step 1:Using a unibit enlarge the brake line exit hole in the F-1072 Fwd Fuse Bottom Skin to 5/8 Diameter as called out in Figure 1.

Step 2: Install the AN837-4D 45 degree Elbow and AN924-4D Nut onto the WD-1021-L Landing Gear Mount-Left as shown in Figure 1. Using the Landing Leg Socket as reference, orient the fitting to aim down the gear leg.

Step 3: Install a An833-4D Elbow, AN960-716 Washer and AN924-4D Nut to the F-1048-L Fwd Fuselage Rib as shown in Figure 2.

Step 4: Using Figure 1, Figure 2, and the isometric view on Page 36-1, make a brake line from ATO-032X1/4 that connects to the bulkhead fittings installed in Step 2 and 3, and passes through the center of the notches in the F-1084A-L Systems Bracket.

Inboard end

Gear mount end bend around the gear leg tube

Step 5: Slip two SB375-4 Snap Bushings onto the inboard end of the brake line oriented as shown in Figure 2. Slip a AN818-4D Nut and AN819-4D Sleeve onto each end of the brake line as shown in Figure 1 and Figure 2.

Step 6: Double check that step 5 was completed correctly. Flare both ends of the brake line (see Section 5P). Attach the brake line to the bulkhead fittings, and slide the snap bushings onto the notches in the top of the F-1084A-L Systems brackets

Page 36-3

Step 1: Uncleco the VENT DL-10 2.4 degree Flanged Ducts and the VA-175 Heat Duct Tee from the F-1048-L & R Fwd Fuselage Ribs and set them aside. See Page 36-1

Step 2: Note here is where I deviated from the plans and used Scott Schmidt's installation to add the parking brake. Here are the steps I used.

Step 2A: I removed the original bracket and cut off the flange that the AN Fittings went through

Cutting off flange

Step 2B: I clecoed it back on, and with the flange cut off and will re-rivet it back to the firewall. Since the holes were already there I figure it will serve as a stiffener and a good backing for the rivets.

Step 2C: I used the F-1048-F Bracket and drilled a couple more holes in it to mount to the Firewall.

Step 2D: Positioned the bracket over the original bracket and used the holes to match drill into the firewall.

Match Drill holes in bracket into the firewall

Step 2E: Put the Matco Assembly on top of the bracket and drilled two #12 holes using the valve body holes as a drill guide.

Use holes in valve body as a drill guide to match drill the bracket

Step 2F: Put nut plate on the bottom of bracket and used it to drill for an AN#3 bolt.

Drill bracket for 2 AN3 nutplates

Step 2G: Rivet 2 AN3 nutplates to bracket.

Riveting 2 AN3 nutplates to the bracket. Rivet holes where countersunk for AN426-3 rivets

Step 2H: View of back of bracket. The holes need to be countersunk for the dimples in the skin of the firewall.

View of back of bracket

Step 2J: Used the pop rivet dimpler to dimple the firewall holes.

Dimpling the firewall holes that attach the new bracket.

Step 2K: The Parking brake assembly clecoed to the firewall

Parking brake assembly clecoed in position over the old bracket bolted on thru the nutplates with AN3 bolts

Step 2L: I had to dig up a couple of 1/4" fittings from another builder. Need them with 1/4 " pipe thread at one end and flare fitting at the other.

Fittings

Step 2M: Fittings screwed in. I am just going Cleco them for now and rivet them later after proceeding to fit the tubing in step 6 from the valve down the tunnel.

This is where I returned to the plans from the Book

Step 3: Using ATO-032X1/4 create both the left and right brake lines as shown in Figure 1.

Here is where I got into a problem. The book refers you to installing the parts of the brake system after finishing the firewall however it seemed the the fuse bottom section needed to be pretty mush finished. Gear Mount etc. in place. I had riveted everything together when I started the brake lines, and it was very difficult to work in the tunnel area. I would suggest you install the lines before riveting the center fuselage ribs. Do it while they are just clecoed in and that way you can remove one rib while putting the lines and cushion clamps in place on the other one and have much better access to where you are working. I had riveted them in place and ran into the following difficulty.

I started with the left, here are the pictures from the left install. A couple of suggestions where I had trouble because of access into the tunnel area, in the next step installing the cushion clamps they are hard to get at, and I had trouble getting the screw in them. On the right side I am going to make sure I have run the screws through the nut plates with a little bolube on them before trying to install the clamps so they will be east to turn.

Line beginning at the park brake valve

Here is where the line goes down to the bottom of the tunnel and passes through the first cushion clamp

This is the turn at the bottom where it bends and goes aft thru the second cushion clamp. I was unable to get the screw started in the forward nutplate and due to the rib blocking it there was no way to replace it at its present location so I drilled another nutplate just slightly aft of it where it was accessible and put in a new nutplate. That is why I recommend you make sure all the holes in these clamp nutplates are easy to install a screw in by running one through before installing the clamp.

Looking aft to where the 3rd and 4th clamp hold the line and then attach at the rear fitting where it attaches through the rib. I have run the screws on the right side in with some Bolube on them so when I install the cushion clamps( they are hard to see under the clamp) they will start and turn easily. Again if you ran these lines before you rivet the ribs in permanently you could remove one while you working on the other side and I believe it would be much easier.

Here is PDF picture with some notes on it if you run the mouse over the little yellow note it will expand the text.

Fellow builder Lance Johnson came over and gave me some help on some line bending he has finished a real nice RV-8 and is flying it a lot.

Here is the first bend on the right brake line coming off the parking brake body.

Right Brake Line coming down the firewall

Right Brake Line going to fitting at end of tunnel.