Cut out the rotted section of floor by the door on Saturday with the assistance of a friend & her circular saw & jigsaw. To make a decent-sized patch, we cut about a 1'x4' section. The rot was actually worse further forward to the point where I could push a screwdriver straight through the floor.
I cut off either the head or the shaft of about half a dozen floor bolts with a cut-off wheel on the angle grinder. That was entertaining. Here is an exciting action photo:
You note I am wearing goggles and gloves. I could've used a long-sleeved shirt though. Ow.
Got some wood for the floor - I bought OSB, oriented stranded board, rather than plywood. Seemed pretty good to me. My friend cut it using the old pieces of wood as a guide and it test-fit in the gap perfectly. Screwed and glued the cleats after that.
On Sunday, finished the floor patch. The new section went under the shell no problem, glued & screwed it to the cleats attached to the existing floor, and then put bolts through to connect the floor to the shell, and the floor to the frame underneath. After putting in the five or so that were there originally, I decided, why not overdo it and put in another 20ish. Actually some of those were to connect the shell to a section a little further forward that's a little rotted, not bad enough to repair and not anywhere anyone ever stands, but just some reinforcement.
New floor screwed in:
Bolts on the underside, and the cleat (with the glue dripping off it):
Also some bolts in the old floor to connect it to the frame closer to the joint with the new floor. And a few bolts at the edge of the step to fix it in place. Basically, not like too many bolts is going to hurt.
New bolts into the step frame:
On top then used wood filler to fill the gaps and some of the screwheads and assorted holes, and also where the original floor had flaked up a bit. All of this will be concealed under the new floor. Anyway, with all those bolts the new section of floor is rock-solid, and so is the shell by the door, and the strain is all out of the section of skin above the doorframe where it had cracked. So basically, problem solved.
New floor with filler all around it:
Four things before that section is finished: clean and paint the frame sections I can get to underneath there; apply insulation to the bottom of the floor; replace the belly skin, and sand the floor surface level for the new flooring.
Also took off the curb-side awning:
The brackets for this were also the reason the floor was rotten. I'm happier without it although I guess in theory shade would be nice.
I've been thinking about putting the grey and fresh water tanks under the floor between the axles.
I can now see that the drain from the shower is actually above floor level, which means there would be plenty of slope to run it to a sub-floor tank, and because the dump outlet is right at the back, even if the slope from the tank to the drain outlet isn't that great, I can raise the front of the trailer with the tongue jack to create more of a slope. So I think that could be quite workable.
Another thing we did (and when I say "we" I mean I made another friend do it) was trace out the patterns from a bunch of rotted plywood sections of the original interior, remove any fittings, and then toss it in my car for the dump. This reduced the amount of useless junk getting in the way considerably.
And then finally we (and once again I mean, mostly, the other friend) put new foil-bubble-foil insulation on the insides of the sections of skin that were exposed. We put two layers of insulation, the first one glued to the outside shell with gorilla glue, which should act to prevent condensation on the inside, and then another on top of that just stuck on with mounting tape, so there's a little air gap. Then some foil tape in places to seal some of the edges.
Insulation:
To reduce the amount of conduction transfer I might put mounting tape or foam tape down the ribs where the interior skins connect, so there's no actual metal-to-metal contact. Of course this is about 10% of the entire interior, but I might as well do this section the way I'd want it all done.
Anyway, a good weekend, especially the floor. For a while it's been all demolition and it was nice to get some progress towards one little piece being finished.
Oh yeah, and here is the new rockguard on the front window:
The Airstream nameplate is just sitting on the window sill, not attached to the shell yet.
I think it looks pretty good, although there's no lifting hardware yet. It's about the same weight as the original fiberglass, very easy to lift.