Heads up! Brake lines rubbing

[Mich48041]

Wayne,
Just because the brake lines and bolts are touching does not mean that the bolts will wear a hole in the brake line. There has to be relative motion between the parts for that to happen. Since all parts are stationary, the only concern is motion from vibration. I do not know how much the brake lines will vibrate.
Here are some suggestions: Remove the cushion clamp and bend it in such a way to maximize the distance between brake lines and bolts. Elongate the cushion clamp hole to move the brake lines closer to the wire bundle. Replace the AN4-4 bolts with AN4-3 bolts. Smooth the ends of the bolts so that there is no sharp edge. Put 2 thick washers under the bolt heads. If there is still a concern, drill holes in the panel above and add wire ties or even two more cushion clamps. Good luck.
Joe

[Mich48041]

Wayne,
I sent you a private message.
Joe

[dick seiders]

I suspect all have the same issue as we build to the plans. I've been thinking about it ever since first noticing months ago at brake installation. Now ready to button up the front pan so it's a good time to deal with what will likely be a problem somewhere down the road. I plan to bend the brake line bundle adel aft to add clearance. If that fails will add a umhw block spacer to move the brake line bundle down about 3/4in. Additionally if I am still anal about it will coat offending bolt tips with silicone to provide a cushion should contact ever occur. If I had it to do over I would consider routing the brake bundle aft of the wiring bundles eliminating the chafing possibilty.
Dick Seiders

[rsipp]

You might also be able to use a 3/16 ID alum tube spacer under the adel clamp long enough to clear the bolts. This would obviously require a longer bolt in the adel as well. I've seen this on production airplanes several times.

Dick Sipp
Assisting a new -12 builder
RV-4
RV-10

[GDS]

I wrapped this section of the brake line bundle with a split, 4" long piece of heavy duty rubber hose and hose clamped it in place. (Same idea as used on the fuel supply and fuel return lines where they come together under the fuel tank) Isolates the brake lines from the bolts, nutplates and control cable housings.