ISO Board Lightweight Teardrop - The Build

[TomsTwin]

Hi, I have started the build as a separate thread. After finally getting together enough materials, I have begun my build. You can find a full collection of photos in my gallery at http://www.mikenchell.com/forums/album_personal.php?user_id=8732
So, the idead was to build a lightweight, expandable teardrop. After some thinking and research, I found a product called ISO board, commonly used for roofing. It is an extremely sturdy foam that comes in 1" to 4" thicknesses. Each side is covered with a fibrous paper. My idea is to epoxy the outside with glass mat. the inside will just have epoxy. The attached paper readily soaks up the epoxy. Whle doing this, I will also embed supports and roof tracks.

I am using a Carry-On trailer with a perimeter rail. My thought is to bolt glue and bolt hte construction to the rails.

So... here we go.

Tommy

[Juneaudave]

Looks like your off to a good start. From the pics...it looks like it cut real well!

[TomsTwin]

Hi...

Thanks. I did mess up the edges a bit since my Dremel wouldn't cut to the depth I needed. So I continued with a razor. Bad move. I tore it up!!!!

So, I will have o smooth it out later.

[eaglesdare]

This is great. I will be watching for all updates. Please post as you make progress, I am interested in your build.

[NebraskaTeachr]

This looks like a very interesting build. I wish you the best of luck with it and hope you have as much fun as I did with mine.

Tim

[ARKPAT]

My trailer is not the best looking but along the same lines of insulation panel construction. Here are a few pictures below. It constructed entirely out of French Door COUPONS ( factory cutouts of the windows in French Insulated Doors ). The fastening system is NERF EDGES and SELF-TAPPING SCREWS sheet metal screws. Doors and windows are framed with wood and secured with longer self-tapping sheet metal screws. All joins are glued with Gorilla Glue for a leak-proof joint and a secure joint fastening. You can really stand on top of the TTT and walk accross it without worry. I had all of the panels seen inside of the trailer on the roof of the trailer ( 20 panels - 10 fiberglass and 10 steel clad ~ 400# )........







Good luck on your build it will be lite and strong.




Pat

[glassice]

Might I suggest you add a LOT of 1/8 holes are the glass will pop louse .We have been building are trailers this way for years

[TomsTwin]

Hello All,

After bad weather delays and general busyness, I have gotten some more done on my ISO board foam insulation trailer. I have rethought the roof extensions and have cut channels in the flooring and side walls. Here are a few pics. More are in my gallery...







GlassIce... Thanks for the advice on adding 1/8" holes. Furtonately, I haven't epoxied any major portions yet.

Once most of the pieces are cut and fit, I will come up with a strategy for glassing and piecing together.

Thanks... Tommy

[Arne]

pegging the pieces together sounds like a good idea. drill a hole, drop in some epoxy, stick a dowel in it and it should last forever.

[kennyrayandersen]

I’m not exactly catching your corner joining method, or why you imbedded the wood strips (going to screw something to that later?). As you have noticed, the foam is brittle, and the small exposed edge, after you router, is very prone to cracking (you should be able to stuff some glue in there and use a bit of scotch tape to temporarily ‘clamp’ it.

[TomsTwin]

Hi kenny,

The corner above is actually a bit of a mistake. This has become the back of the trailer. It is about 1" too long, so that one rabbeted edge will be removed. I will post a close-up of the wall-floor joint in about a week or so. I have already had to patch some cracked edges with epoxy, so I am quickly learning about the brittle-factor. Oh well...

Also, I am embedding wood strips into the foam for bolting to the framee. I will coat the bottom of the floor with rubberized roof patch and also bolt it through these strips to the trailer.

I have done something similar with the side walls and will bolt throught he wood to the trailer side rails.

[TomsTwin]

Hello all,

I finally got to the point of epoxying the first wall.

After cutting all the channels for the Aluminum tubes through foam and wooden wall supports...



I checked the fit for the 2"x4" wall cross beam...



This beam will sit over the galley wall and act as a support for the galley huricane hinge.

With all pieces fit together, I cut out the door shape. I then cut out a 1.5" x 1" rim from the door to glue back into the door opening. This rim will act as a seal placement and a drip ring.



a close-up...



Finally, I epoxied the inner side of the passenger wall. The final coat was died white.



A close-up of the door opeing corner with rim glued back in place and glass mat at corners.



That's the progress thus far. I hope this all works and doesn't blow apart on those Montana highways.

Thanks... Tommy

[skuntz]

As if you don't have anything else to do but update your thread, eh?

I am really curious as to how the project is progressing. I had similar thoughts about using iso panels based on some reading I have done on composite construction and building one off canoes and kayaks.

I see you are using mat fiber cloth... what's your thinking on woven cloth over iso boards?

Steph
(totally a newbie only in planning and dreaming and obsessing stages of my build)

[TomsTwin]

Hi Steph...

Actually, I did use the woven cloth over the ISO board. In the above pic, I had some glass mat lying around and used it just for this small area. Woven is the way to go over the walls.

And, I sure do have some updating to do. I have taken current pics, but need to upload yet. Thus far, I have the floor down and the side walls and the front all glued in and bolted to the trailer. I just purchased some 1" ISO for the galley wall. I need to get a small bar sink to place in the middle of the wall so it is accessible from inside or outside. My big change is to rethink the expanding woof and top wall extensions. I have decided to attach hinged wall boards from the side walls to the roof that will straighten as the roof is raised... sort of like folding a piece of paper. Then the aluminum supports will keep the rof up and prevent the top walls from folding in. Still redesigning this.

I'd like to see your kayak project. I love kayaking, so I am curious...

Thanks, Tommy

[skuntz]

Have read about but done only little projects with composites. I see that one offs for canoes/kayaks often use a pliable foam (ie diviny cell or core-cell) sandwiched between cloth (fiberglass/kevlar etc) to provide structural support. So to my mind when I see you laminating foam to fiberglass I see structural integrity without weight. Google Ray Jardine kayak building (he is known for diy ultralight backpacking equipment)
There are also "dome homes" built in the same way as you are constructing your trailer and in that case a spray polyethylene foam is blown over a frame and then covered with a sealing material similar to fiberglass.
How are you finding the iso board as a material to work with?
You complained that the paper and foam are sucking up a great deal of resin. Any thoughts on changing materials slightly to a non paper backed foam board and ironing (yes I said ironing) the surface so that there are fewer voids for the epoxy to fill - they (whoever the hell they are) suggest doing this when working with pliable foams in canoe building for that very reason.
Boy you've really got me thinking - I should be sleeping - got to leave for work in 6 hours for a 12 hour shift and here I am blathering on.... these teardrop trailers seem to do that to people.
Steph