Hello All,
Retired engineer and construction project manager [South Georgia boy who has somehow wound up in SoCal] who has decided to design and build a small travel trailer. Totally rebuilt a 1969 Shasta 17ft Starflyte last year; that was a good learning experience; don't need that one again. My new project is built on a heavy duty 6' x 10' utility trailer. All amenities and not working to a budget. After reading a zillion web posts and manufacturer's information, I got an idea of what other folks are doing on their projects. My walls are 1/4" oak ply interior skin on a composite of 1" x 3" pine members with 1" XPS fillers and Foam Fusion as the adhesive. ALL the joints are with Kreg fasteners and TB3. My headroom is [was] limited by the lintel height of my garage. After looking at the TAXA Cricket, I have decided to build a tilting roof to give standing headroom in a major portion of the trailer. My brother, the master craftsman, says, " just like you Glen, make the first project you do as complicated as possible". Seems OK to me. The roof will be hinged at the rear. There will be an outside standup galley, all other amenities are inside: toilet, shower, hot and cold, 12v and 110v. The last cabin panel will be installed this week, and the interior cabinetry will start. The "stuff" has started rolling in for installation.
What is not decided, and which I need help and advice on is the exterior "skin" and the adhesive to be used. Seems like the "usual suspects" are GG or TB to attach a fabric skin of cloth to the foam or plywood. I have conducted a number of experiments, and have spoken with manufacturers, and have settled on Foam Fusion as the adhesive to bond the foam to the wood. Foam Fusion is specifically made for foam, but will also bond to porus materials; and my test so far are excellent. Have learned that it is essential to perforate the XPS with the Warner wall paper removal roller, and not just lightly, go heavy. The big question before me is: what fabric to use on the exterior of the cabin and roof, and what adhesive to use between the foam / wood and the fabric. Would love to get your comments and counsel on this. Experiments todate useing TB3, Foam Fusion, canvas and FRP insect screen indicate a preference for FF and insect screen on the XPS. The tear-off tests are about the same for each version [you have to really work at it], but the bug screen lays flat, is smoother and seems to provide greater impact resistance with two layers; am going to run a section modulus [bending] test next week using a strip of XPS with TB3 and canvas versus FF and bug screen on both sides; this will be on either 1" or 2" XPS . The roof will be 2" XPS sandwiched between stringers of 3/4" x 2" poplar, and will have a "skin" on top and bottom sides to provide stiffness. The exterior skin will get a good primer and paint, maybe a marine topside paint. Am about to need a Path Forward on this question. There it is folks, would really not like to step into the you-know-what on this critical issue. Who has gone before? My greatest concern is strong long time adhesion between the fabric, adhesive and the foam. Thanks, Glen