Learjet 45 Simulator Project

The rough shaping and sanding is done. Final sanding requires a guide coat, so I found some old acrylic paint I had sitting around and used that. What, you thought I wanted a purple plane? Only if I was Prince or a rabid Vikings fan.

Learjet 45 Simulator Shell with Sanding Guide Coat Applied

Just a quick update on my progress:

Phase 1: Rough trimming -Complete
Phase 2: Rough shaping -In progress
Phase 3: Foam putty (Fill in bubbles and other voids) -In progress
Phase 4: Final shaping (Various automotive block sanders) -Not started
Phase 5: Foam hardener -Not started
Phase 6: Paint -Not started

Learjet 45 Shell Foam Shaping Progress

…took longer than expected, but the Bondo finally cured, and I was able to fill the shell wall voids with foam. It was more than a little surprising that it took so many cans to get it done- 12 in all. The clerks at the local hardware store where I was buying all this spray foam were, not surprisingly,  giving me the twenty questions routine. I’ve learned that telling the truth in these situations is not always the best policy.

It needs to stabilize for a few days before I can start trimming and sanding it down.

Learjet 45 Simulator Cockpit Shell with Foam

Smelly and messy is all I can say about that stuff. Make sure you get some ventilation and/or wear a respirator when working with it.

In preparation for the foaming process, I am filling the grooves (fluting) I made in the outside of the hardboard wall pieces with Bondo to help strengthen and keep their shape if  things ever need to be disassembled. The filler foam will be sprayed on top of that and then shaped with hand tools and automotive finishing sanding blocks (used for body fenders and such).

Learjet 45 Shell (Now with Bondo!)

I decided to take a break from the interior for now. I’m just getting over a nasty virus and I need something to do where I don’t have to think too hard about it.

I’m attaching cardboard to the frame voids so the spray foam doesn’t stick to it. The foam sticks to the panels installed on the inside and they are removable.

I feel like I’m back in art class playing with toothpicks and glue.

Learjet 45 Simulator, Shell

The walls are painted! It’s strange the way the uniform color on the inside changes my perceptions. Although I know it’s just Masonite hardboard, it feels like I’m inside a real airplane now.

Bring on the foam!

Hi,

I finally got my camera working again. You’d think by now I’d know what I was doing

The inside walls have been split and joined using bolts. It makes them smaller and easier to handle upon disassembly. Hard points have been added to the horizontal stringers. These will be used as the attach points for the outside covering.  I could probably just use the existing support skeleton for attaching the covering, but I am worried that it will introduce splitting or some other unforeseen ’problem’. As a precautionary measure, I took this route.

The next step is to figure out how to keep the spray foam from sticking to the structure–other than to the fluted inside walls, and begin shaping.

Hey all,

I’m just about ready to paint the inside walls. After that it’s placing the hard contact points on the outside for the outside covering and then filling the voids with spray foam. I’m having camera issues, so no pictures for now. I’m sure what I said makes no sense without pic’s. Sorry.

So as some of you know, Ron used aluminum flashing, spray foam, and fiberglass to create the outside of his shell. I’m modifying the procedure a bit to hopefully be able to take mine apart in smaller pieces.

Instead of using flashing, I’m using 1/8-inch hardboard to cover the inside. It bends easily with the grain, but against the grain, not so much. I don’t need much bending against the grain, but I don’t want the covering to distort the frame. To solve that problem I fluted the panels using a table saw to assist with their flexibility. This seems to be working well, so I may use this technique on the outside of my shell too. To get the hardboard to bend more easily in both directions (compound) I was thinking I could create fluting in both directions. The good thing about this approach is that one side of the board is still smooth. There are limitations to how much you can bend it, but I think it will work.