Newbie builds a foam toy hauler/camper

[Pmullen503]

I found adding water to the gg joints caused heavy foaming and swelling, just running a bead of gg and leaving it works fine. Of course I'm in a damp basement, it may depend on your local humidity levels
I would save some money though and do the fabric coating bonding with titebond II, save gg for foam to wood or foam to foam joints..

When I say a light coat I mean basically what you can't scrape off the surface with a plastic putty knife. Picture a puddle of GG the size of a quarter spread out to 1 or 2 square feet. Anything more than that is a waste on foam because the foam is so weak. Once it's that thin, you want it to foam up to bond to the foam surface so I spritz it with a mister.

Speaking of TB2 and canvas, I had a test piece of canvas stuck to wood with TB2 and then another piece of canvas glued to it to simulate the bond I'll get around the perimeter of my platform. Bottom line is the canvas to canvas bond is as good or better than the canvas to wood bond. Bonding my wall canvas to the 2" of exposed canvas around the perimeter of the platform should be adequate. (I have already painted the bottom of the platform with roof coating so I can't really wrap the canvas around the bottom.)

 

[GPW]

"so I can't really wrap the canvas around the bottom.” .... Sure you can , just add more roof coating ...

 

[Pmullen503]

True. I suppose I could unbolt the platform from the trailer and raise it up for the canvasing. Of course, canvasing the edges first and coating the bottom was supposed to avoid that step. I'll have to try using the roof coating as an adhesive for canvas just to see how well it works. I should lift the camper off the trailer to paint that bottom edge, not to mention the trailer itself. I would like to repaint it but that will have to wait for warmer weather.

The way I'm doing things may seem strange but there are reasons. Where I work is in the back of my business where it's warm. But the trailer can't stay there during the day so I drag back to the garage when I done working on it. So glue drying times etc all have to conform to this daily 65F-20F temp swing. (I can't stink up the place either so that also dictates materials and methods.) Also, the platform itself is my flat work bench, so getting it bolted to the frame was necessary.

 

[Pmullen503]

Here is the first of the shelves. 43" x 84", 1/8" hardboard skins, 1 x 1.5" wood perimeter and cross pieces, gaps filled with 1" foam. Wood to hardboard glued with TB2, foam to hardboard with GG.

Second skin glued on and trimmed with flush trim router bit.

I'll let it dry for a couple days and see if it's rigid, and strong enough.

 

[KCStudly]

It may flex some when you pick it up by just one corner, but once you mount it to your glides that will all be moot. What you have there will absolutely meet your needs, I am sure of that!

 

[Pmullen503]

I need to do some woodworking before I can start assembling the sides. For the Yakima rack supports I'll laminate (2) 1.5" x 2" wood supports with a 3" wide piece of 2" foam between them. When that dries I'll section in a couple plywood plates to bolt the Yakima mounts to. The door frame will be 1.5" thick wood framing with 1/4" plywood inside and out. I leave a lip on the inside for a seal. The door will be 1" thick wood with 1/4' plywood skins. That will give me 1/4" for the seals. One of the Yakima rack mounts will be incorporated into that assembly. I'm thinking of putting Wiley windows on either side. Maybe in the door, maybe not.

I ditched the rear hatch in favor of barn doors as KCStudly suggested. The ease of use trumped any improved aerodynamics (plus only one hurricane hinge required.) Just have to figure out how to mount and hinge them. It would be nice to mount the doors between the sidewalls to get the gap out of the wind while towing.

 

[Pmullen503]

Here are the supports for the Yakima racks and rear door hinges. I sectioned in two 1/2" plywood plates to bolt the gutter rails to for the Yakima racks. The screws are there to hold them in place while the GG dries. I'll remove the screws so they aren't on the way when I drill for the gutter rail mounts.

 

[Pmullen503]

I glued together the parts of the left side. I used the trailer platform as my work table. I clamped the parts together by screwing down 2x4's at either end and tapped in wedges to squeeze the parts together. It turned out the extra long side members for use with a bumper came in handy when it was time to clamp everything together.

While the glue was drying I spent about a half hour steaming the stamped in writing out. The writing was pressed in almost 1/16" and would definitely have shown through the covering. I used a piece of wet cloth and a hot iron. Lay the wet cloth over the writing and press with a hot iron. As long as steam is being formed you're OK. As soon as the cloth starts to dry out the temperature can go up rapidly and melt the foam. The foam will expand back to it's original size and the depressions will be gone (works for dents too.)

After that I gave it a quick sanding with 80 grit on an RO sander. Then I covered what will be the inside surface with my heavy muslin. I rolled on a coat of TB2 and smoothed out the fabric, then came back with a second coat of TB2, and finally rubbed it down with my hands to get rid of any bubbles or wrinkles. An occasional mist of water kept the surface from getting too sticky. I worked with about two feet of cloth at a time.

 

[ghcoe]

While the glue was drying I spent about a half hour steaming the stamped in writing out. The writing was pressed in almost 1/16" and would definitely have shown through the covering. I used a piece of wet cloth and a hot iron. Lay the wet cloth over the writing and press with a hot iron. As long as steam is being formed you're OK. As soon as the cloth starts to dry out the temperature can go up rapidly and melt the foam. The foam will expand back to it's original size and the depressions will be gone (works for dents too.)

Good idea. I will have to remember that. I filled mine in with spackle. Most where not very deep like yours though luckily. Could be because I had the trailer out in the sun some before painting.

 

[Pmullen503]

Good idea. I will have to remember that. I filled mine in with spackle. Most where not very deep like yours though luckily. Could be because I had the trailer out in the sun some before painting.

Raising the depressions turned out to be more important than just for cosmetic reasons. I had a few bubbles when the glue dried and they were where there was a low spot in the foam. I was able to get them mostly stuck back down by applying a hot iron (with the release liner from some UPS sticky label stock to keep the glue off the iron) but the temperature that the glue was reactivated was very close to the melting point of the foam. I got one divot where I let things get too hot and the foam melted underneath. The spots that lifted looked to have less glue so I'll need to keep that in mind when I cover the other side.

 

[ghcoe]

Going by your description above it sounds to me that you laid out the fabric and then applied two coats of TBII. The proper way would be to roll on the TBII then lay the fabric over the glue and roll the fabric into the glue. No glue on the outside of the fabric. If you laid out the fabric first and glued over the top you are probably starving the foam surface of glue which could be what is causing your bubbles.

 

[Pmullen503]

No, I rolled the first coat of TB2 onto the sanded foam, applied the cloth, then another coat of glue on the cloth. The idea was to saturate the cloth with glue so the cloth/foam bond wouldn't be starved. I'll get a scoring tool and try that on the right side. I'm not that worried about the inside, but I would like to get this sorted by the time I cover the outside.

You know, for RC airplanes we use water based polyurethane to adhere cloth to foam. Lay out the fabric and the poly soaks right through. I wonder if anyone has tried it with canvas....

 

[GPW]

PM , I believe we’ve all been trying to get the absolute Best bond between Foam and canvas (fabric) and the TB2 has proven to work very well so far ... If you’d like to independently “test” the poly/foam/fabric join , we’d really appreciate hearing about it !!! 

 

[Pmullen503]

PM , I believe we’ve all been trying to get the absolute Best bond between Foam and canvas (fabric) and the TB2 has proven to work very well so far ... If you’d like to independently “test” the poly/foam/fabric join , we’d really appreciate hearing about it !!! 

Maybe I'll try it on the partition wall.

 

[Pmullen503]

Here's a couple shots of the side door frame. The frame was made with 1.5" x 1.6" wood to compensate for the 0.20" plywood (not 0.25"!) I suppose I could have sanded the foam to match but then I'd have a gap for my shelf runners. The part below the Yakima racks are only 5.5" instead of 6" like the other three. Seems I forgot to compensate for the loss due to the saw cuts. Still hoping to get everything from 4 pieces of 4'x8' foam sheet. I used a hot wire to cut the 2" foam down to 1.6"

The door is 28" wide which was the biggest I could fit in and not get too close to the wheels. The bottom sill has a 5 degree angle out to shed water. I was pleased that the corner pieces (with matching 5 degree cut on one side) came out right on the first try because I had to laminate a special 3.5" x 1.6" board and didn't make enough to screw one up! I used the fancy "IntegriPly" underlayment and was disappointed that the edges chipped when I routed out the opening. I opted to leave the plywood on inner opening. I'll cut it out after it's covered and hope it doesn't chip as badly.

 

[KCStudly]

For splintery wood, or when transitioning cuts from across to with grain, if you score your cut line with a utility knife it helps prevent chip out (credit GPW for helping me with that little tip ).

Similarly, on end cuts you can back up the edge with scrap clamped flush to the work, then just run off the work piece onto the scrap.

 

[Pmullen503]

I covered the right, inside surface with muslin. This time I made sure there was plenty of glue on the foam before I applied the fabric. I also misted the fabric with water to get it to relax before I stuck it down. This time I had no bubbles. Once I get the partition wall covered and the window sectioned in, I can start assembling the sides.

I plan to use a Wiley window but I have a question about how to finish it off. I'll make it flush on the outside but how do you finish off the inside? The walls are so thick; do you just leave the overhang, make the window frame taller, angle the foam sides and top? I couldn't find a reference with a good photo of a Wiley window in a thick foam wall.

 

[Pmullen503]

Now that Christmas is over I can get back to work. I haven't cut out the inner door opening yet. I plan to leave it in until the sides are glued down for strength and stiffness. I did cut out the corners of the door opening with a router and a circle jig. It worked much better than a saw with no chip out. I cut the bottom of the door opening since there wouldn't be room for the router once the sides are glued down.

I dry fit the sides and bulkhead to check for problems and work out my clamping scheme. I found a problem with the location of the bulkhead; it was right where one of the bolts for the Yakima side loader brackets will go. Moving it forward would move the hatch hinge location forward (unto the curved part), but there isn't room enough to move it back without crowding the side door. I may have to have the bolts straddle the wall. I'll want to make the hatch longer too. I plan to have a table I can fold down when the hatch is up but the fixed wall is too high on the plans. I'm glad I didn't start gluing things yet!

 

[rowerwet]

I have a few ideas but have done only Wiley windows in plywood so have no actual experience.
Make the door of two layers of 1" foam glued together. Cut the inner piece to fit the whole window assembly, and the window hole in the outer face to be the frame the window and screen seal against.
A thinner outer layer of 1/2" foam might be better still, I'm planning a foamie this year, the doors will be framed in wood, and probably be skinned with 1/4" ply.
You could also cut through the door and add a frame of wood or foam to the outside of the door to seal the window, this way the support angles for the inside would be less obtrusive. I saw a barn with windows set into a 2x4 wall that way. There were no brackets intruding past the inside wall, just the top of the window when opened. The supports were simple diagonal strips nailed to the inner frame.

 

[Pmullen503]

I have a few ideas but have done only Wiley windows in plywood so have no actual experience.
Make the door of two layers of 1" foam glued together. Cut the inner piece to fit the whole window assembly, and the window hole in the outer face to be the frame the window and screen seal against.
A thinner outer layer of 1/2" foam might be better still, I'm planning a foamie this year, the doors will be framed in wood, and probably be skinned with 1/4" ply.
You could also cut through the door and add a frame of wood or foam to the outside of the door to seal the window, this way the support angles for the inside would be less obtrusive. I saw a barn with windows set into a 2x4 wall that way. There were no brackets intruding past the inside wall, just the top of the window when opened. The supports were simple diagonal strips nailed to the inner frame.

I think I understand what you mean. I do want to limit the amount the frame protrudes from the wall and I had thought to limit the frame to 2" thick so the windows will be flush on both sides, at least when closed. That leaves me with closed, a 1x18" opening at the top (wedge between the glass and screen,) or remove the glass completely for the full 12 x 18" oval.

I'm ambivalent about partially raising the glass and wedging it in place which would leave the end of it kinda hanging out in space. I should probably mock it up and see how bad that is.

The door is another issue, I may just not do a window there and put one in the wall on that side and two in the wall on the other side. Do (3) 1x18" slots seem like adequate ventilation?