Aft Lower Firewall Attachment

[Dick B in KY]

Does anyone have info or a picture on how the aft section of firewall under the belly attaches. I have no clue how this is suppossed to attach, no info in my manual. I think it should be removeable to some extent, to facilitate access to rudder pedal hardware. Thanks.

Dick B

[Dorsal]

Are you building a 7? Tail or nose dragger?
If it is a 7 the answer is it doesn't attach and can't be removed (without removing other little things like the engine). If you have a nose wheel you can sandwich the trailing edge between the nose mount and the fuselage, the sides are captured by the boot cowl.

[Dick B in KY]

Sorry about that Dorsal, it is a SS 7 taildragger. So it does not attach on the aft edge?? I can see the sides capture under the cowling flange, but the rest just flaps in the breeze.?

Dick

[Danny]

Dick,
If you bought the firewall forward kit, the instructions will be in it. I will try to post some photos tonight that should help.

Basically, you have to epoxy tabs to the lower fuselage tube & rivet the firewall to the tabs. Again, if you bought the firewall forward kit, the material should be included in the kit. Cut holes in the bottom of the firewall where the hardware for the rudders are so you can get to the nuts if ever needed.
Danny
Hopkinsville, Ky.
SuperSport
a few months away from completion...hopefully

[HighWing]

I have a IV and am just about at that point. The original IV manual said to drill into the cross tube and rivet it. I did that on the first one and finding the exact center of the tube was a challenge.

The IV also has the external radiator and it is mounted through the floorboards with spacers to the fabric surface. I agree that being able to get to the pedal mounting hardware is a good idea. In my first one, the service letter regarding the cracking of the pedal weldment came out and I had to drill out the rivets to be able to remove the pedals. This time around, I plan on securing it just like the radiator is mounted. Three bolts through and into the floor boards.

Lowell

[Dorsal]

I remember going through this and was told the tabs where not necessary but I am sure they couldn't hurt. You could just run two bolts through the bottom plate into the nose mount locations, this seems to provide plenty of support on my plane.

[jtpitkin06]

I have an instruction sheet that came with my firewall kit. It clearly shows the rear of the belly panel 42728.000 attached to a fuselage tube with 14 “hanger brackets” builder fabricated from stock 42918.000. The brackets look like miniature versions of EMT tubing clamps.
The brackets are bonded to the fuselage and the belly pan gets riveted to the brackets with 95002.000 SS rivets.
The negative thing about this installation is, it covers the rudder pedal hardware with a riveted panel. That makes it impossible to inspect the nuts holding the rudder pedal brackets at annual inspection time. Instead of rivets, builders may wish to use PK screws with Tinnerman nuts on the hanger brackets to make the belly panel removable.

John Pitkin
Greenville, TX
SS7

[Mark]

I skipped the hanger brackets and just mounted the aft end of the firewall using screws through two of the holes for the nosegear attach points.