Sparky
Well Known Member
I'm just starting the fuselage on my RV-7 and am almost to the point of preparing the firewall for riveting. I plan to install the optional MATCO parking brake valve.
While reviewing the archives, it seems most builders use the standard brake line firewall penetration location and stiffener plate (F610TD) specified in the plans. Since I haven't drilled the holes yet, I found that if I lower the firewall penetration location by about 1 1/2" I can mount the parking brake valve directly above 90-degree AN bulkhead fittings (and below the cross brace stiffener angles) using very short (about 2"), lengths of 1/4" straight aluminum tubing between the valve and the AN bulkhead fittings. This would avoid having to run tubing over the cross brace stiffener angles. Also this would allow me to fabricate a larger (vertically longer) stiffener plate (in place of the F610TD) on which I would mount the valve, AN bulkhead fittings, and cable bracket and would utilize the existing prepunched rivet holes in the firewall (plus some addition ones).
It appears that by lowering the firewall penetration point by only 1 1/2" I would still have plenty of clearance on the FWF side and clear the engine mount, braces, etc. It also appears that I would not create any interferrence problems with the rudder or brake pedals.
Am I overlooking something? Does anyone see any problems with this plan?
While reviewing the archives, it seems most builders use the standard brake line firewall penetration location and stiffener plate (F610TD) specified in the plans. Since I haven't drilled the holes yet, I found that if I lower the firewall penetration location by about 1 1/2" I can mount the parking brake valve directly above 90-degree AN bulkhead fittings (and below the cross brace stiffener angles) using very short (about 2"), lengths of 1/4" straight aluminum tubing between the valve and the AN bulkhead fittings. This would avoid having to run tubing over the cross brace stiffener angles. Also this would allow me to fabricate a larger (vertically longer) stiffener plate (in place of the F610TD) on which I would mount the valve, AN bulkhead fittings, and cable bracket and would utilize the existing prepunched rivet holes in the firewall (plus some addition ones).
It appears that by lowering the firewall penetration point by only 1 1/2" I would still have plenty of clearance on the FWF side and clear the engine mount, braces, etc. It also appears that I would not create any interferrence problems with the rudder or brake pedals.
Am I overlooking something? Does anyone see any problems with this plan?