TERRA6, Van cab and chassis 7*14, 4" Polystyrene

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The roof.
The roof and the unknown.
Build it strong enough to hold together yet light enough without overloading the walls. And adding solar roof panels. Allot of them. Didn't know at all how or what but I took a shot at it.
T trusses underneath but would have to inset some boards for mounting points of the solar on the top of the roof, under the PMF. I had contemplated a solid plywood roof, or metal. But thought that if need be, could always add it later. One advantage of foam and PMF, I could add to it at a later time easily. Could skin with aluminum on the walls or roof. Or just a metal roof skin. Add more bracing and support if the initial was insufficient. Could add on the fly, and boy was I flying along on this build. Going like gangbusters to get it done, the pressure was on from all sides. And still determine what and how to build it as I was going along. This wasn't going to be a long, slow build. It was get'r'done time.

So for the potential of solar roof mounting, I inset 1*6 cedar fence boards. Cheap and as weather resistant as possible. With all the mounting points, the potential for water infiltration was high and cedar is as good as it gets for resistance. Under PFM, shouldn't be an issue but every bolt intrusion will become a leak sooner or later.
In hindsight, would have gone with the new composite boards instead but the bonding to it might not have been so great. Learned that it wouldn't have been an issue and the way to go as we will find out later. Maybe. Hopefully. Time will tell. It's only been a month.

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Flying right along, assembling, building, gluing, compressing, setting and waiting. Great that I had a work table that was just the right size. Convenient.
And able to work outside in the dry and sunny AZ weather. Hallelujah.

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As you can see, I went with PL Premium 3X at $8 per large tube. Did a test first off of wood to the styrofoam and it was great. This took ALLOT of glue and it is necessary to butter and maximize adhesion and bonding. Don't have an exact count yet but it's maybe 20-30 tubes, over $200 of glue. And not counting the caulking that I used to fill the seams and seal the joints, over 50 tubes of that which I got mostly at $1.
Am confident in the adhesion of this glue, I think. Maybe. Hopefully.
Only time will tell, as it is unproven.
But any, and all glue will eventually fail as it goes through the thermal and weather cycles of hot and cold, expansion and contraction, weather temperature extremes and exposure, aging and decay. And if the glue doesn't fail, the substrate it's adhering to will decompose and commence delamination. You see it all over on the fiberglass skinned RVs. And they have the best tools, adhesives and working conditions. So I'm realistic about this. It won't be permanent but needs to ideally last for the duration of the reliability of the mechanical components of the rig in this case. Those building on a trailer, hoping for longer lifespan since a trailer will last longer than an engine and suspension etc... Good luck.
But there really is no such thing as luck, only choices and reality.
Hoping that I buttered enough for Max adhesion and the durability of the glue in my application will be equal the lifespan of the rig. Only time will tell.
The only comment that I can make at this time is that this glue sets very hard. There is no flex to it which might be an issue in future after expansion contraction cycles. If the styrofoam has too many and to much of these cycles, will the glue hold and for how long is the question for which we are completing life cycle testing upon at the moment.
On my current, completed and built rig damnit.
Umm, why didn't you build one first ten years ago to prove and test this? Why do I have to be the guinea pig?
Insanity my friends, insanity.
And because George was busy doing god knows what 10 yrs ago. Exactly what were you doing back then George that you didn't get on this sooner?

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More pics fyi.
I was able to manuever the panels solo, on and off the deck and around as needed. Bicep power.

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At this stage you will notice the back notch cutout. Count the sheets and notice the discrepancy that in the introduction I said 12' and the panels are 14' so 3.5 sheets.
Initially I decided upon 12', the length of the frame. But upon thinking about it, for $20 more, I could gain 2 ft more and not have to extend the bed or chassis by cutting up or lengthening/ raising to 14'. It would allow me to push the Murphy bed I had planned for back there and gain 2 ft of interior space. Since there was no load or weight going back there, could hang out of the back. Tricky because the walls are styrofoam but with an inner frame, could suspend or support the bed from the floor. And it gave me the cool overland lite look i was looking for.
And the potential to do something very unconventional that might add to the coolness factor. A surprise to be shared later.

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Build and glue a section, glue and canvas the section.
Maybe even get excited and impatient and paint a section. And then the wind picks up and dusts the fresh paint job with a gazillion loose styrene beads.
But damn it looked good freshly glued. The canvas was straight and smooth. I patted myself in the back and was beaming with pride. Great job.
Prematurely. Didn't dry so nice. The seams and weave were pretty much straight but my joints showed through and dried with a crease there. Darn.
I must say that I have hung wallpaper before and that this was very similar. Also have a textile background in industrial fabrics so this was right up my alley and not worried about this.
For material, I used the Harbor Freight drop canvas. Cheap and available locally. Bought 5, 9*12 of which only two were seamless in the middle. Given more time, would have picked through for seamless but the closest store was 25 miles away and I was on a deadline. One makes do. I also was able to successfully cut out an overlap seam with a razor blade once it was hardened and dry. That is an option if one wishes to take the time to do so.
One of the cloths had a 6*8" unwoven fault which I was able to work around and cut out when doing the nose cone. At the reasonable price of $16, can't complain.

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Ah yes, the pasting glue that I used was TB3 as it has much better water resistance than TB2. Or claimed to.
Regardless I went with it and did like everyone had said, dilute 50% with water. So I was so happy and eager to be at this stage. 50%, easy peasy. Ga dok goes the glue into the pitcher, half full. Ga dok goes the water the rest of the way. Happily stir and we're off to the races pasting and laying cloth, yay!
But damn, there's a problem. This is way too watery. This can't possibly work and be sticky enough to hold canvas trying to be sucked off while going down the highway at foamie land speed record. It's too damn watery. Maybe I got the mix ratio wrong. No, everybody was doing 50% dilution. It just wasn't right based upon my past experience and references and compared to the initial consistency.
So I thickened it with more glue. Would it be enough?
Damn, had no experience with this glue and everyone used TB2. Damn, damn, damn. What to do?
Damnit I'm pushing forward in my eagerness and will see how it goes. Well the next day I tested it and not promising, cloth lifted easy enough. Not the greatest adhesion. Some four letter words ensued vehemently. Every syllable was spoken strongly and properly enunciated.
Damn all this work and effort wasted, start all over? How? Fudgicles. Might have said something else.

Ok should have tested, time to reassess. Turns out TB3 which is the good waterproof stuff is much more watery and than TB2. Would think it would be the opposite, it's not. Thus it needs to be diluted much less. Damn, cause it's more expensive too. So I did a test at this stage with dimpling and not and full strength versus a 20% water dilution and had to wait a day to dry. Damn, I was on a tight schedule, complete build, places to go, people to see. Lost a day waiting for this.

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The imperfections in the surface will show through the cloth. As most are using new sheets of polyiso with no seams, not an issue. Mine was the complete opposite and this is where you pay for it. I had used, dinged panels with three seams on each side that needed to be filled and smoothed. That lightweight exterior spackle filler that some use is almost$20 for a small bucket and I was going to need a lot. Another budget killer, what else could I use that would be cheaper? Hmmmm, there is this cheap caulking at the dollar store that might work. Used that before as filler, might work here. Off to the dollar store to pick some up. Damn it was 25 miles away as was the closest HD. Walmart was only 8 but I was going to need lots of caulking so as cost saving and pick up other things at the same time. More lost time. Damn.
There's lots of cussing when building something for the first time. It just goes with the territory. When you work alone, nobody around anyway.

Found that this caulk dried fairly hard which is good for flat smooth results. Filled well enough and so far so good for less than half the cost of the spackle I figure. I've gone through allot of caulk trying to smooth my seams. Damn, will have to eat ramen for the rest of the month but found it on sale last week, 8 for a dollar. Works wonders on the weight loss regimen though.

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I also fiberglass taped the seams with three 2" wide tape strips per seam and smooth caulked over that for strength like the drywallers do. Will it work? Don't know. You know what to do.
I also was in a hurry at one stage and did a quick tape and seam fill followed right after with a cloth paste without letting the caulk dry. It will all dry I convinced myself and should be no problem, flat dry and smooth. It didn't and paid the price for not wanting to wait the extra day for drying time. I had to cut corners and it shows on the smoothness of my joints/ seams. Still trying and hoping that I can do this now. The sheets came out mostly decent, but the seams are all noticeable. Debated to leave alone and accept or work it and do better for a long time. Chose the later and wonder if I should have left well enough alone. Damned if you do, and damned if you don't. More cussing

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As you can see, started to paint right away because, why not? While waiting for one to dry, would paint the others one, build efficiency. Go go go, had to get'r'done, schedule and people wanted me out of there at this stage.

Opened up my 27 gallons of paint to see what I had. As this were leftovers, combiners into 5 gallon buckets, mix of whatever, who knows what I had? I had 3, 5 gallon buckets and 12 single gallons of everything imaginable. Mostly Sherwin Williams. Turns out, 12 gals was white, great. Don't know if exterior or interior. 5 gals of a grey, 5 gals of a sand tan, and the rest were various colors of beige, tan and off white. Well the firsr color coats didn't matter, only the last few so I went to town and splashed paint all over. Oh what joy, fresh new coats on cloth, getting closer to final reality. I like to paint, the results are instant and obvious. Makes me feel better even though I end up with as much paint over everything in the area and myself and clothes. Clothes will be part of the final budget cost as I had glue, paste, paint all over me and on a few pairs of shoes, pants, tshirts and jackets. Was chilly in the morning and at the end of the day.

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Pasting the cloth method.
After my poor initial adhesion, my test results weren't impressive either. Even with the dimpling, and overnight, adhesion wasn't impressive. How to correct and assess.
So I lifted the canvas on the wall that I had already done about 12" from the edge and stoked more glue full strength. Theory being that the edges will lift and be a problem first. The inner could probably get away with less.
Hopefully. Maybe. You know what to do.

Dimpling showed no benefit whatsoever and if anything, was negative, with a hole not being properly filled and adhered to. Didn't dimple at all except for an initial small section on one wall. Besides, my cheap dollar store massager, which I used for a dimpler, broke and wasn't going to stand up to the rigors of the job. Chuck that idea.
It was only an instrument for more cussing.

I finally decided, based on a guess, that 80/20 TB3/ water is what I would use. Sounds about right, right?
Hopefully, maybe, you know what to do...

Mix it up and slap it on all over, sounds like a sex tape, but I digress.
Paint the TB3 on with a 4" brush, need to work it into the Polystyrene which isn't smooth like polyiso. Do like George said, do a 12-15" by full length 7' section of glue on, first the foam, spray the cloth with water, brush the glue into the cloth section, unfold and smooth onto the foam. George uses a roller which works for him. Initially I used a 12" wide plaster mud spreader which was ok but tended to pull or catch the cloth and sometimes distort the alignment of the weave. Found that, wearing the cheap rubber faced gloves, would just flatten and smooth with my hands, would work well initially, then go back over it with a 4-5" plastic putty spreader to ensure good adhesion contact by pulling the spreader over the cloth surface. Hands on, enjoyed this part. No cussing involved. Until the next day.

If you pulled the cloth too much while laying or trying to straighten the seams, that while drying, could contract and revert to it's original, uneven lay. So it's important not to stretch the fabric too much when laying and pasting as well as ensuring that it's straight and aligned before you start. If you have to pull too much, it will distort the fabric and give uneven results. The fabric weave will be pulled and crooked. And the seams which are seen will show as crooked and obvious.
This can be dealt with by cutting out the seams, lots of paint to hide the weave and that will minimize the problem.

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So at this stage, I've got three walls assembled, pasted and painted and I'm itching to assemble. Ok, the side walls no problem, hoist up onto the the bed. Only needed to go up 30".
But the roof.
The roof.
How the hell am I going to raise it up over 9' in the air and then set on down on two flimsy styrofoam walls being held together by a few sticks and some overpriced glue?
I was thinking about this as I was gluing and painting. Didn't know how heavy it would be. The walls were lighter as I had less reinforcing wood. Could move those myself with some effort, balancing and dragging or keeping one end on the ground. The roof however had 4x more wood and much heavier, plus had to elevate this way over my head. 150+lbs.
Crane? Got one I can borrow?
Payloader or front bucket on a tractor? Got one I can borrow?
Leverage, how about leverage? How did they build the pyramids again?
Got any ideas? I had one crazy one and the owner wasn't around. She still doesn't know

[Projector]

See that side wall laying on the ground?
I didn't put it there. The wind did. And it remained in one piece. Thank goodness and evidence that maybe my design and method was designed sufficiently to handle the stresses of the job. Hopefully. Maybe. You know what to do...

The weather decided to turn winter at this point and the wind blew at 20+ mph from the north for a couple days. Just as I was painting with styrofoam beads sticking to everything and as I was ready to assemble. Was perfectly calm before that of course.
Well, I was on a schedule, places to go, people to see.
Got to get'r'done. Damn wind, more cussing. This was serious. Ever try to assemble a kite in a tornado?
Well I had to lift heavy panels but big and light enough to sail in heavy winds. Or at least test the effects of gravity, momentarily, till it comes crashing heavily to the ground. Once assembled, glued and set, I knew it would be sturdy. By this time it's Dec. And the winter winds have picked up. Winter is coming and so are the white walkers.
I was starting to look and feel like one with the long hours and pushing to complete, stress and cussing n this solo, one man journey. I felt like Don Quixote battling windmills.

The assembly was critical and fragile, wind would not be helpful. And yes, I put the roof up on the garage with the help of the passing by neighbors 6'+ kid who was big and strong. Thank God as I'm only 5'7". Together we got it on the roof at dusk when the winds calmed but made sure to screw it down as there was more wind forecast. Plan was to then just slide it onto the walls and hope that the whole thing would not collapse on top of me like a huge mousetrap.
Maybe.
Hopefully.
You know what I did...

[ghcoe]

Glad to see you finally got the forum to work again.

Thanks for the mention.

I am assuming that everything is still holding together ok.

Thanks for sharing your build here with us.

[GPW]

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