PMF/Foamie Rolling Coffin Construction Technique

[Zilonox]

tldr; Can I build pre-fabricated XPS foam and poor man's fiberglass (PMF) panels and then construct my hard-sided tent on wheels, or should I construct first and PMF afterwards?

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A little background: A year ago I bought a small, used 4x6 Tractor Supply utility trailer that already had a four foot tall wooden box built on it. I turned that into what amounts to a hard-sided tent on wheels (or coffin, as my wife puts it). It's just a place to sleep with a little storage space for essentials (camp chairs, cooler, camp equipment). The box that came with it was not water tight, and in an effort to get it converted quickly and cheaply, I did my best to insulate and waterproof it. In October, we had just about a month of rain followed by some unusually warm weather. When I went to prep the camper for a December camp out, I found white fuzzy mold growing in the places that leaked the most. I pulled everything out and cleaned the mold, but I think it's time to just completely dismantle the thing and start over (something I've wanted to do from the beginning, but time and cost were against me then).

Even before I bought the trailer, I'd been looking at builds here on tnttt, and foamies really caught my attention, especially since it's a small trailer I wanted to insulate the camper for winter camping anyway. I've read/watched much on PMF, and it appears that folks do all construction first and then skin the entire thing with PMF afterwards. Is it inadvisable to build the individual sides/roof complete with PMF first and then put it all together? (My plan is to use 2x2 or 1x2 for framing and fill with XPS sheets.)

Why would I want to do things that way? Mostly due to space considerations. I have space indoors to store panels, but not the full sized camper, while I work on it. I would also like to still use the camper as is while I construct the new one. Obviously, my main concern is preventing leaks at the panel seams and corners. Would glue and screw be enough? Perhaps glue and screw with weatherstripping/butyl tape?

[GPW]

Z’, Build it the way you want , either way works, use what way works for You !!! You already know what you want so you’re good !!!

“ Obviously, my main concern is preventing leaks at the panel seams and corners.” … We need to talk about seams , corners and “reinforcing strips" …

You have a sketch of what you want to do ???

[Pmullen503]

Part of the reason to assemble first and canvas the assembled box is for fewer seams on the outside. You will have overlaps or extra pieces at the corners or other seams. But for example I went from under the floor, up the side and onto the roof on each side with a roughly a 2 ft wide strip down the center of the roof to bridge the gap. No seams on the sidewalls except for vertical strips at the corners.

I covered the insides of the my panels before assembly because it was easier to do when they are laying flat and I used a lighter muslin fabric for the inside and so less worried about the panel warping. After assembly I added 8" strips at the corners to tie it all together.

Some people preshrink their canvas to reduce the warping or cover both sides at the same time and let it dry vertically.

Either way, you'll definitely want to add PMF strips to all your covers to thoroughly waterproof them and structurally tie everything together if you cover them first. I'd skip the wood perimeter on the panels altogether. Just glue the panels and cover the seams with PMF strips.

[KennethW]

I canvas my wall lieing down. Letting the canvas run wild at least 5" a also I stay back with the glue 3" on the outside to round the corner. I used no wood in the walls (1 1/2) the door frame when glued to the wall gives me plenty of rigidity. Hint, Ratchet tie straps for holding down the roof when gluing it on to the walls. Hope this helps.

Sent from my Moto G (4) using Tapatalk

[GPW]

That looks Super !!!

[linuxmanxxx]

Love the soft cover over the galley idea and where the hell did you get that awesome door?

I like how you left the roof edges flat. Did you sand it to round it or just fill in the gaps and say to heck with it?

[KennethW]

Love the soft cover over the galley idea and where the hell did you get that awesome door?

I like how you left the roof edges flat. Did you sand it to round it or just fill in the gaps and say to heck with it?

The soft cover is a pickup tonneau cover. With a few poles it becomes a awning.
The door is a cut down full view storm door with a wood insert and a window from a aluminum pickup topper. (Got the door from habitat restore for $50 I had the window)
The roof-wall corner has the roof overlaping the wall then rounded with a palm sander. with the canvas overlapping both ways there is no need to fill in the roof bending kerfs.
The flat edges on the roof is the ends of the solar panels that form most of the roof.
There is no wood above the floor of the drop floor. (Just 1 1/2 foam and canvas).
The bars above the door pulls out for a side awning(rain cover) with the support tubes going across the inside for the curtains(cloth hanger rods)
I am glad to answer any questions you may have.

[linuxmanxxx]

Is your foam to foam gorilla glue?

[KennethW]

I put the panels to gather with Loctite PL window door & siding Polyurethane sealant. Really sticks to almost anything but it does not seem to melt the foam like other sealants. It take time to cure to a rubber like sealant(like silicon but does not meld the foam and a lot better bond). It is hard to get a nice smooth finish as it is really sticky.
If you like the inside color I got the canvas for $5 a yard(6 foot wide) https://www.bigduckcanvas.com/12oz-heav ... y-seconds/
Other colors https://www.bigduckcanvas.com/12oz-heav ... y-seconds/

The reason I when with the tonnaeu cover galley hatch is that it does not require a strong hinge support that a conventional hatch does. (1x4 plastic board screwed to the solar panel and glued to the foam wall)

[GPW]

Wow !!! I think that galley hatch idea is Brilliant !!! Saves a Lot of weight and hassle ,and yes , no hinging, and it’s an awning too , like the Old West Stage Coaches , the “soft cover" on the back … NICE !!!

Aesthetically it may be considered the “Convertible “ of teardrops …