Brake Line Gear Transition

[Archer39J]

I'm working the belly panel and figuring how I'll attach the panel under the door, but I can't see a good way to route the brake line. How have other folks done it?


gear_brakeline_2.PNG

gear_brakeline_1.PNG

[AKKen07]

Dave, this is what I have done. It’s the best I could come up with after SEVERAL iterations.

[Battson]

My brake lines to through where the front hinge is. Need to be near the hinge to ensure they don't move too much and stress the system when in use, but they also need to stay out of the way of the fairings. I used the soft-covered lines (the black ones with rubber insides) so they can just rub against the metal without any worry.

[whee]

I can’t find any pics of how we did ours and a description probably won’t help much but I’ll try.

All our brake lines are pre-made AN4 braided SS hoses from Summit. We used a 45* bulkhead fitting at the top of the gear leg that points toward the center of the airplane. The brake like enters through the belly skin and is covered with a RV rudder cable fairing.

[Archer39J]

Thanks guys. I might have to go to a 45* bulkhead fitting but I'll have to finish the belly/under door skin wrap to be sure. The forward cutout seems the easiest.

This is my 2nd iteration too, took the opportunity to switch to SS PTFE from the rubber aeroquip.

[Nev]

Dave, mine are similar to AKKens above. You can see two bulkhead holes in my photo where I originally had bulkhead AN fittings (now lightening holes), but removed them after installing the Park Brake on the same bulkhead. This works well and the fittings are now 90 degrees to original. The fitting on top of my gear legs face forward as yours do. This gives a short flexible brake line. Sorry - I disassembled everything today (in the rain!) so don’t have that flexible brake line in place for a pic.

Left side looking forward:

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Looking aft at PB valve beside gascolator:

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[James]

Mine are a bit like Nev's - but further out board. My airframe has a vertical tab there, and so I used that along with a small L-bracket and a p-clamp to support the tube. Then a rubber grommet through the alumunium bulkhead at station B. I had steel braided teflon lines, and I put two layers of shrinkwrap where it transitions through the bulkhead.

Then from the bulkhead, it snakes around to the 90degree bulkhead elbow, oriented N/S in line with the gear. I'm not flying yet, and I'm also not sure how this tube will exit the fabric.

James

[noema]

Bumping this thread.

I planned on running my lines like AKKen07. Start at the 90 deg AN fitting at the leg and then run them into the fuselage. When I simulate the rotation of the gear leg all that rotation gets transmitted to the next fitting. My brake lines are from Pegasus Racing. They flex but have almost no give rotationally.

I am concerned the rotation of the gear leg may cause unnecessary strain on the AN fittings on either side to the point the connections will get loose.

Is this specific to my brake lines. Should I have gotten some with a swivel end? Different type? Maybe just much longer? Connect them 90 deg to the gear leg?

Input appreciated.

[AKKen07]

If I understand what you’re saying I think you can solve it pretty easily and you’re already on the right track. You might be able to see that my lines in the pictures make a 90 degree bend from the gear leg to the bulkhead where they transition to plastic lines. That bend turns the rotation of the gear leg into simple flexing as the line turns inboard. Does that address your issue?

[Mark Goldberg]

Hello Stefan. Usually the transition from the gear leg top to fuselage is with some kind of flexible line. Yes the gear leg moves. But not that much up at the top. I do not 100% understand your question. Mark

[Paul Johnston]

I have one -3 hose from master to brake cyl.- it passes through rubber grommets at top of gear leg- 48” works good with the patrol-mine are premade by Earls peformance and sold on Amazon. When I had the flying school with the C152s , the hard line on the gear legs would crack and leak. All those hard landings!