Newbie jumping into building a foamie. Have several question

[Krusty]

I'm in a bit of a peculiar predicament that leads foamies to be quite intriguing for me beyond the having a lightweight vehicle.

You see, I'm a cheap bastard. I constantly research the best price for things and smack myself if I wind up buying something for even a few bucks more than I could have gotten away with.

At the same time, I'm really not hurting for money by any means. Both my wife and I work at well paying jobs and we have no children so our savings accounts are ripe for plundering.

So for this build I'm going to have to balance out lightweight and quality with letting me feel like I'm getting a deal. I already picked up a Harbor Freight trailer on sale and with a 25% discount coupon. It's cheap as hell but it could be lighter. Considering I'm building out of foam that's not as big of a concern for me. I just read one guy in the big thread mentioning that torsion axles could cut a big chunk of weight out.

I am opting for fiberglass because, despite being cheap, it seems like it may be a worthwhile expense for adding some longevity and durability to the build. Paint and canvas seem to be working quite beautifly but fiberglass should trump the strength and durability while only adding maybe a couple hundred bucks more to the build.

It seems like nobody has been looking too deeply at the polyiso foam so far so I may be able to provide the opportunity to add a bit of a new spin and experience to foamies here. I haven't drawn out my plans yet but I think I'm going to go with 1" polyiso foam with fiberglass and polyester resin. The foam will be for a bit of insulation and to give a base structure. The fiberglass will provide the strength. And, as mentioned previously, I'm going to aim to make it a pop-up style to give some head room. My primary decision I need to try to make first is if I'm able to get a bed that runs perpendicular to the trailer in order to get some extra floor space. My wife is 5 feet and I'm 5'6" so it may not be much of a stretch to have a notch for foot room hanging off the side somehow.

[Mary C]

Thanks Guys, Krusty the foam you are talking about is the kind that you can take your finger and rub it off the stuff becomes like powder? covered in metal sheeting? if that is the stuff you are talking about I might suggest that you experiment with it first? I have heard that it will disintegrate into a powder in heat over a period of time that is why they put on the aluminum . You will be doing an experiment for all of us if you take a piece and put in the sun or oven and get it hot then cold even the freezer. then hot again to simulate the constant changing of temps and you might want to call the manufacturer and find out what kind of glues will work on it and .............You get the point I just don't think that has been done I know it is cheap but you understand that all that has been done with the pink and blue foam already and I am not sure why but someone decided not to use it. so far we have done our homework and we have done the experimenting on pink and blue. I am not saying it could not be used I just don't know anyone who has done the experimenting and made the phone calls on it. Maybe I missed it. The foam you suggest might work but I would check with the manufacture and see if the chemicals you want to use will work Like you said No body has been looking into it. it is also curious to see if it will work with glues you might have to do some experimenting and even calling the glue manufacturing companies Chemicals can do funny things. Look at the fact GPWS foamie was in a hailstorm and afterward just being in the heat fixed the indentations and just a little paint fixed the marks. we have learned because we discussed the experimentation and shared our work. Good Luck and we want to hear your experiments and get the information.

Mary C.

[GPW]

QUOTE: “ You see, I'm a cheap bastard ...” Well you certainly came to the right place !!!

[Krusty]

I poked at the polyiso foam a bit at the home depot. It is, indeed less held together than the pink or blue stuff and looks like it can rub off. I'm definitely going to snag a sheet and do a little experimentation to see how it holds up. In my research I found that polyiso appears to be the kind of foam used to make surfboards, but they use a higher density (and much more expensive) version of it. It's also far more resistant to temperatures as it doesn't burn until 400+f. This isn't to say that something else won't happen though.

If I could conclude that it'll withstand regular denting and vibration without turning to powder, I think it'll be a worthwhile item to go with when using fiberglass. We'll see once I get all my gear together.

[GPW]

JMHO, I don’t believe surfboards are made of the iso’ foam ... (too brittle) Mostly polyurethane or EPS foams ...

[mgb4tim]

Many boards are polyurethane, which can accept both epoxy and polyester resins. The beauty of polyester surfboard resin, is that I don't believe it needs a clear coat since it's already uv stable. There are uv stable epoxies, but pricy.

[Krusty]

Does anyone have some online resources where I may be able to purchase foam board? In particular, is there another kind of foam out there that I could use polyester resin with that isn't quite so fragile?

[Lonewolf42301]

Does anyone have some online resources where I may be able to purchase foam board? In particular, is there another kind of foam out there that I could use polyester resin with that isn't quite so fragile?

With some hunting, it should be available in your area, if not at the big box stores, maybe a specializeduilding supply store or insulation contractor? Good choice on avoiding the iso bnoard, as I know from experience that uv rays and age will deteriorate the foam. Its in my house as a sheeting under the cedar siding.

[Lonewolf42301]

Just found some answers on Krusty's thread.....

[Mary C]

Krusty, if you plan to glass may I suggest one inch thick sides and doubled 1/2 inch for the top and hatch. You probably can do that with the pink foam and get away with that if you use some 1x2s on the inside frame. The thing is you might get some little cracks. You were talking about the aluminum coated foam when the outside is removed I was told that the stuff will just disintegrate. The Heat in the summer will cause that and the builder said he is replacing it on homes because it becomes a mess after a few years. He is confused why it is still sold. Just thought I would mention it because I was in the HD this last weekend and thought I would check it out.

Mary C.

[GPW]

Best stick with what we KNOW works ...

[Krusty]

Thanks for the advice.

Is there a kind of foam that is more stable than polyiso that won't get eaten up by polyester resin? And, of course, where could I find it cheap?

By going fiberglass I'm thinking that 1" walls would be plenty of thickness for insulation and stability. I'm hoping that'll cut down on cost and weight by a good bit.