Foamie Jeep Camper Hardtop

[atahoekid]

I too had some small dings under my fiberglass skin that disappeared after a while. The compressive strength of foam is pretty surprising. And as with almost any material, if you take a hammer to it, it's gonna leave a mark, some permanently. I don't worry too much about the hammer test, it's not a real life scenario, if it survives minor dents and dings without major issues, I'd say it's got possible value as an outer skin. I'd go for the solid board, but there's nothing wrong with smaller scale testing to see if it works. It does two things 1) It either proves or disproves your theories/concerns and 2) It helps you figure out the best methods for joining, covering, adhesives, etc. We built this topic on theories being tested... We'll just add your test to our warehouse of knowledge. Go for it, your kids would love to do some "destructive testing"

[Wobbly Wheels]

I recently did a simple test just using primer and a few layers of newspaper as a skin. We're about a month into the wet season now and it's borne the brunt of it with no sign of degradation whatsoever. I haven't given it a "hammer test", but I think would be plenty rigid for a skin, especially when applied to both sides of the foam. Were I planning a trip over Niagara Falls, I wouldn't build a barrel out of it...but a foamie ? Sure.
That's with 3 plies of newspaper: if you could get it completely saturated, a heavy paper would probably make a great skin. You would need something pretty runny and multiple applications means that it would stick well to itself: 'the mix' would probably work pretty well.
I also tested out some Ram Board (floor protector paper), which is thicker but less dense than kraft paper, and couldn't get acetone-thinned epoxy to penetrate all the way through (though vacuum infusion would probably work).
Given what it's produced for though, it's no surprise that it was more difficult to wet out ("Exclusive Spill Guard™ technology")

[GPW]

Consider this ... If you laminate many layers of corrugated cardboard together into a Thick sheet ( each layer perpendicular in grain to the last , like plywood ) , that does produce a Strong structure ... The weak link is the outer skin which is still just one layer of paper ... obviously , a Thicker layer (s) of paper on top would much increase the skin strength ... the addition of some fiberglass drywall tape mesh wouldn’t hurt in the high stress areas ... cover that with some old bedsheets and you’d have a pretty solid structure , with some insulating benefits (trapped air) ...

Multiple layers of cardboard is what they use to make all the cardboard furniture ... that and folded tubes ... anything’s possible really ... just another plant product ...
W2, newspaper , recycled , is always a Good thing , eh !!! ...

[atahoekid]

Brings my mind back to the discussion we had on the big thread (I think) about paper mache as a covering. I think we were convinced that it would work well and could be used to hide/strengthen joints and seams as needed. Not sure anyone ever actually used it in a build. Also wondering how quickly cardboard layered up in a plywood fashion, the adhesive and the skin starts getting heavy? I wouldn't think it is a light as foam but done right it could be pretty damn strong. The SIP/composite panel is an amazing structure. The sum is greater than the parts.

[redveloce]

I did some more searching and found that there is a sister product to Hexacomb called Falconboard that is designed for signs and mounting instead of cushioning packaging. It comes in many thicknesses from 1/4" to 4". I was actually able to locate a local distributor for Falconboard! I got pricing for the 1/4" and 1/2" 4x8 sheets, and I'm waiting for the local rep to call me back with information on possibly getting some samples so I can do some testing!

http://www.sgpweb.com/products/product.asp?pm_id=731

[eaglesdare]

cool, keep us updated.

[GPW]

The Fine Print : "CONDITION OF USE AND STOCKING
Shelf Life: Falconboard (Print/Mount/All-White) has a shelf life of 12 months after receipt from Sonoma Graphic Products. Storage (new and partially used rolls): For quality reasons Falconboard (Print/Mount/All-White) should be stored and converted under conditions of 35-65% relative humidity and at a temperature of 10-30°C. Storage of open rolls: When an open roll of media is not being used » remove the roll from the printer » cover the roll with a plastic bag to protect it from contaminants » if you are storing it on end, use an end plug and tape down the edge to prevent damage to the edge of the roll » do not lay sharp or heavy objects on unprotected rolls and do not stack them."

[redveloce]

Yeah, it's a paper product. It will have to be sealed well.

[KCStudly]

Some of those precautions are related to maintaining the condition that suits the printer device. They are much more finicky than a glue roller! I didn't study the spec.'s, just saying.

[redveloce]

I talked to the rep, and he seems pretty excited about the project. He said there are several other materials that I may like as well. Were going to connect next week, and he's going to get me samples of all of them.

[Wobbly Wheels]

Kewl...while you're yakking with him, can you ask if it's available in Canada ?
Might be fun to play with.

[redveloce]

So after considering my options, I've decided to go with foam instead of cardboard. I just can't get past the possibility of catastrophic failure if the skin were to become compromised and allow moisture penetration. I may think differently if I lived in the South West, but living in the Seattle area, I definitely need to take moisture into consideration!

Can someone explain how to change my thread title to "Foamie Jeep Camper Top"?

Has anyone tried skinning foam with plastic, such as ABS? I believe both are styrene based, so it may be possible to actually bond them instead of just gluing them together. I've read about using lacquer thinner to bond ABS to ABS. Spreading on a thin layer like you would a glue slightly melts each piece of ABS, making them one once it solidifies. Perhaps the same thing would work with extruded foam?

I've used ABS for making brackets, wind deflectors, etc. It is easy to cut, shapes easily with heat, and extremely tough and resilient. I used 3/16" ABS sheet for my wind deflector, and it was WAY overkill. I would probably use 1/8" or maybe 1/16" for skinning over foam. I'm going to pick up a few samples of those thicknesses from Tap Plastics this afternoon, but I still need to acquire some XPS to do my testing.

I'm also excited about the vacuum forming possibility of ABS and other thermoplastics!

[Wobbly Wheels]

I tried bonding some styrene sheet to foam using styrene solvent cement (model glue) spread thin. I wanted to see if I could make a hard plastic panel for cabinet doors and hatch boards like the thermo formed acrylic cabinet doors that you see in kitchens.

The problem I had was that the cement was too aggressive. Even putting it on the plastic first and waiting before applying it to the foam, it ate the foam before it welded. I couldn't think of a solvent that would thin the glue without eating the foam so I switched horses and went with latex contact cement instead. Then I figured that, if I'm going to use latex contact cement, I'd use thin ply for hard panels so that the glue could get a better 'bite' so the plastic was out too.

It would be a great problem to solve because it would eliminate more wood from our builds.

I don't know if you can change the thread title, but if your switching from a cardboard to a foamie camper, I'd say that's certainly a big enough difference to justify a new thread.

[KCStudly]

Can someone explain how to change my thread title to "Foamie Jeep Camper Top"?

Go to your first post in the thread (OP) and use the edit feature (upper right hand side). This allows you to edit the subject line which will change the first post and any new posts. If you change it again it only affects the first and subsequent posts; the posts made in between keep whatever subject line they had when they were created. At least that has been my experience before some of the recent forum changes.

[redveloce]

Perfect, thanks!