Firewall
I’ll be starting to work on the boot cowl and before I do this, I must position the firewall accurately. While checking the Northland CD about measurements and installation, I noticed that the flange for the firewall as well as the ridges supplied by Nick did not seem to be installed correctly
View attachment Firewall 12365.pdf
See the firewall drawing #12365 from CD
Someone (I just can’t remember his name…really sorry) on one of the posts explained the following concerning the installation of the firewall:
‘’
Firewall ridges (or bumps) should ideally face forward to the engine (engine side) and the back side should rest flat on the steel tubing going across the airframe.
Now the flange that goes around the firewall…The top part will wrap around the outside of the firewall (facing engine) and as you go down on both sides there is a notch at the bottom where the flange now goes inside the firewall. The purpose of this is that when any fluid (water / oil) splashes onto the firewall, the fluid will run down the firewall and as it gets down to the bottom the fluid just going to drip off but if you have a ledge / flange there, there is a risk that the fluid can drip inside and get back into the airplane…’’
So, here is the firewall from Nick and see what I mean. Either facing forward or back side, there is something wrong. I explained the problem to Nick and right away a new piece of metal was coming my way. Nice to deal with the Smith!
So, I downloaded, printed & glued together the 16 pages in order to get a full size drawing for accurate measurements
Made a plywood template for the exact radius
...And notched it.
All drilled and ready to install the flanges.
Done.
Centered on the fuselage!
More to follow
Dan