SonexBuilders.net

Hey all...

I was looking at my lower firewall yesterday, and noticed that the factory "cutouts" for the engine mount attach angles and far larger than they need to be, and leave some pretty large gaps:



Mine look this way on both sides; these are the factory, unmodified cutouts. Is this normal, and has anyone made any stainless steel patch pieces to cover these gaps, or do you just fill in with high-temp sealant and call it good?

Those gaps look about right, Andy. Some high-$ aeropace grade sealant with fill it right up. Have a flashlight holder in the cockpit and the sealant shooter on the firewall side in a dark hangar...

N111YX wrote:Those gaps look about right, Andy. Some high-$ aeropace grade sealant with fill it right up. Have a flashlight holder in the cockpit and the sealant shooter on the firewall side in a dark hangar...

Coolio...I figured this is just another case of "experimental aviation is not rocket science, despite any other similarities". :lol:

Seal it up with this stuff, works great:

http://www.aircraftspruce.com/catalog/a ... 0caulk.php

I just did this job.. put a thin bead between the sheets on the rivet lines as well. A friend told me of his experience with an alternator failure in flight on his RV-8.. entire cockpit filled with smoke within seconds. I also intend to put a dab into each rivit to seal everything as best as possible