Firewall Forward

Well, it looks like I can't come up with any reasons to wait any longer for this task, so it's time to rivet the firewall recess into place. I carefully cleaned all the contact surfaces with MEK. Then I used the rest of the sealant that came with the heater valve to apply sealant to the flanges on the recess. There was just enough to go all the way around and fill in the corners inside the recess. But after the riveting was finished, I needed to use some high-temp red RTV to seal the outside corners and fill in the little gaps near the middle of the flanges. Here's the finished job!

The riveting was all pretty straightforward until I got into the lower horizontal line along the bottom. There's not much space under there, between the bottom surface of the recess and the horizontal flange of the stiffener. I found that none of my bucking bars fit in there very well. This is the second or third time I've been in a situation like this, wishing I had purchased the narrower tungsten bucking bar instead of the thicker 1" square one that I have. I was finally able to use one of my tapered iron bars, and kind of wedge it in there. It didn't work very well, and it took me a long time. But I finally got it done. The rivet tails aren't real pretty, but they do fall into specs and they won't be seen under there anyway. It was also quite narrow in there along the top. But not quite as tight as the bottom. When I was finally finished and the red RTV applied, I was able to put the battery box back on. For good, this time!

Only one more little item remained. See the little hole under the heater valve, above? It's for access to the nose wheel gear leg bolt, if you ever have to remove the nose gear leg. This access hole will allow you to remove the bolt without having to take the engine mount off of the airplane. You can imagine what a nightmare that would be on a finished airplane. Well, I don't need this hole at this time because I can easily attach the nose wheel gear leg to the motor mount before bolting it to the firewall. And that's exactly what I'm going to do. So I sealed and attached the plug, as seen below.

My firewall is far from finished, but I am ready to hang the engine on it! I hope to get some help lined up and get that done in the next few days.

<< Previous | Home | Next >>