Firewall material

The original firewall blanket was old, greasy and didn’t even cover the full firewall.

I did a lot of research on various material to cover the firewall to protect against, heat, flame and sound.

I really liked a material from Aircraft Spruce, but of course it was not FAA approved.

I send a few pieces to a DER for testing and get the test report so now it IS approved on my aircraft.

I cleaned the firewall, cut the material and used 3M V77 adhesive spray to attach it.

Design

I started dreaming about what the final product would look like, so I used my daughters ability to do digital drawing to play with paint schemes.

As you know I’m coving the aircraft in dark blue oratex fabric, so I started playing with White, Silver and Black as trim colors.

I also found a great site called www.aerographics.com that makes vinyl decals you just stick on the aircraft.

Below is the design I think we are closing in on. Note the Big “S” on the tail for Stinson!

Doors

I have really liked the patrol door look and since I had an extra set of doors I thought what the heck!

Example of patrol doors

There are two types of doors, framed and stamped, N97954 originally had the framed doors, but the parts I bought in OK had Stamped.

Framed on Left, Stamped on right

So I cut the cut the bottom panel out, then sanded the doors down and then some light body work.

I should have done this first, but I did a dry fit and the fit very well.

I did have to add some small body work as the doors were a little beat up over 70 some years.

Next will be ordering the dark tint plexiglass. The bottom will be held in with a seal on each side of the glass, and use of backing strips and hardware.

The upper window was originally a two piece window that slid, but I’m going with a one piece window and a Piper like flap window

Old then New

I have no idea if these brake lines were original or now, but they sure were old and brittle. I found a hose shop and had a new set made. Cost wasn’t too bad, about $180 for the 4.

The original hoses had a end that was also used to connect to the frame, but finding that fitting was difficult and if found, costly, so I used an AD832-4D to connect to the frame and the two hoses.

Old hose end in the foreground, and AN832-4D in the background

Soda and patterns

Today, the weather in Dallas was PERFECT, so I got out the Harbor Freight soda blaster and worked on the light surface corrosion inside the vertical stabilizer. Only took about 45 minutes and a lot of dust, but the inside looked great after. Later I took it down to the airport and sprayed the inside with Zinc Chromate Primer (after flushing with water and drying of course).

I also “Dry fit” the OLD cargo floor and front wall to evaluate using aluminum to replace each and the use of Oratex as a side wall covering. I came to the conclusion that I may want to go with the original cargo canvas material, because if I cover the entire cargo area with Oratex, then getting into the aft fuselage may be difficult. I may use a local upholstery company to remake the cargo envelope.

I watched a video on YouTube about using this material used to protect new floors as a great thickness of cardboard to make patterns. Well I gout out my floorboards and made patterns. I plan this week to go to a local meta sales store and see if I can buy aluminum plate that is waste from drop cuts.

Considering everything from diamond plate, to smooth aluminum with anti skid material. Also considering either powder coating or cadmium plating. Stay tuned.

Oratex decision made

Tonight I also made a decision on Oratex. I decided to use the dark navy “Corsair” blue for the exterior and Bright Silver for the interior.

Yes, I plan to use Oratex for all the interior covering, it will be very light and provide more space is it is expressly thin, yet strong. Also easy to install inspection plate and such.

I tried to estimate some rough material needs with some measuring tonight. The material comes in two widths, 42” and 71”. Then you purchase in 1 meter linear lengths.

The 42” wide runs about $68 per liner meter.

Cleveland’s

Slowing working on the Cleveland brakes. Sent off the brake lines to get rebuilt and while they are gone I’m working on the calipers.

I had bead blasted the outsides and cleaned them well, but because the aircraft had sat since 1983, there was residue of the O-ring on the bore of the caliper.

I used some X-50 anti-corrosion spray and a scotchbrite to clean that area up. In the picture below you can just see that ring in the bore of the caliper on the Left and how clean the one of the right is.

Aslo found out Univair sent me the wrong -O-ring for the Piston.