We did run into one snag along the way... we had decided to insulate the doors with spray foam, and our first attempt at doing this didn't go so hot. Basically, I had the idea to fill all the voids in the inner door shell (except for the areas where the door latch mechanism will go) with Great Stuff foam and then cover the exposed, wet foam with wax paper.
Covering spray foam with wax paper to help mold it into place - Don't do this!!!
The thought in my head was that if I had it all covered with wax paper, the foam would expand underneath and nicely fill any gaps, and once it cures I could just peel away the paper and magically have perfectly contoured and textured foam beneath. What really ended up happening was the foam didn't cure properly (it needs plenty of fresh air to cure, and the paper denied it that), and so it ended up as this reduced, goopy mess that stuck to the wax paper better than you would believe! It was a nasty disaster that took a while to clean up. At least I only did it to one door as a test!
We then figured out we could just spray foam the doors and let the foam expand way beyond where it needs to be, and then cut it down to size with a hacksaw blade and the orbital sander. It's pretty wasteful-- we ended up using about 2-3 cans of foam per door and cut away most of it-- but once it was done it looked pretty neat and definitely added some "substance" to the otherwise hollow and flimsy door halves.
Sarah liberally applying spray foam while the doors are clecoed to the fuselage
First pass of foam, curing in place on the fuselage
The door halves after the first pass of foam was cut and sanded down
Close up of R door, showing masked off areas for door linkage. Also, we filled some of the bigger voids (like near the lower front corner of the window) with a second pass of foam
Final pass of foam, Sarah decided to get cute with the leftover and wrote our initials in the respective doors :-) Most of it would be sanded away, but you can still barely see it...
So by this afternoon, we had both right and left doors ready to join their halves together! The next steps involved cutting some pieces of Parabeam fiberglass that was included in the finish kit. Each door needs two 5" x 9" pieces to sandwich between the door halves at the upper and lower pockets. I had never heard the stuff before, basically it's a three-dimensional fiberglass weave that is about the thickness of a piece of scotch brite, and feels kind of spongy. Each 5" x 9" piece absorbed about two pumps' worth of West System epoxy!
The four cut pieces of Parabeam fiberglass weave, two for each door
So with the fuselage door openings masked off, and everything prepared and ready to attach, it was time to mix up some epoxy. We mixed three kinds, measuring in West System dispensing pumps as a unit of measure: (1) a total of 4 pumps' worth "neat" epoxy for the two Parabeam pieces; (2) a total of 4 pumps' worth of micro slurry to slather over the exposed spray foam; and (3) a total of 10 pumps' worth of Cab-O-Sil/Flox mixture to spread around the window and outer perimeters. The Cab-O-Sil/Flox mixture was made to about a "thick oatmeal" consistency, where if you held the cup sideways for a while it would just start to pour, but just barely. Sarah and I established a system where I'd mix up batches of epoxy and stir in the necessary additives, and she'd slather it on to whatever it needed. In this way, it only took us about 15-20 minutes from the mixing of the first epoxy batch to the time we clecoed the door to the fuselage.
R door clecoed (and clamped) to the fuselage
Set up two 250W heat lamps to keep the door warm during curing
We thought about starting on the L door, but we were using all of our spring clamps and heat lamps on the one side. We'll do the other side tomorrow!
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