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Foam fun finding facts

Ok, just got back. 4'x8'x2" Pink foamboard $25ish. Check under INSULATION in the yellow pages (owenings pink or Dow blue) HPI Henry was the place but only had Dow in 1".

Home Depot. Initially, I couldn't figure out why some home depos had foam in different places. The white stuff is in the insulation isle. Available in 4'x8'x2" for $14. It's Stanley's Insulfoam R-Tech and has a white plastic coating on one side, and reflective on the other which would have to be removed. Also in the insulation isle is that other stuff, possibly with the fibers in it. Johnson Manville AP Foil Faced 4'x8'x1" for $13. I don't know if that stuff is safe with hotwire.

Now in the stucco/drywall isle is where I normally see the pink or blue stuff. One homedepo carries the pink, the one I stopped at only has the blue. Both are only 1" thick and probably 2x8'. The BLUE has lines through it (score lines I think they called them). Unless you stay within those lines, they'll have to be filled when you make your object. I forgot to write the price but think in the $5-8 range. I don't know if all areas would have a stucco isle, it's pretty popular down here. HPI has the BLUE and you can specify no lines.

Also if you look under Concrete Forms, often times foam is used as blocks or wall panels.

HPI also had some large 2x3x3' blocks which would save gluing but create a bit of waste. For an interesting foam project see:

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Joel. phx

Reply to
Joel Corwith
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Try your local hot-tub store. I've seen a couple "industrial waste reuse" sites where such places are pretty deparate to get rid of the substantial pieces of foam used to proectect the hottubs during shipping (recall that garbage disposal fees are by volume, rather than by mass...)

BillW

Reply to
Bill Westfield

The "beady stuff" is not actually Styrofoam. It's called Expanded Polystyrene (EPS) in the plastics/molding industry. Works great for nose cones and other structures like bike helmets but not really good for turning. Wire cutting works well if you get some stock that is dense enough. Look for construction grade EPS used in Concrete forms etc... It's about

28g/l density and that is plenty strong. As a bonus these construction panels like "Quad-lock TM" are made with treated EPS so that it's flame resistant. Pieces from TV boxes etc are not dense enough to provide support for anything (16g/l) and a hot cutting wire wouldn't have to be very hot to create nasty holes everywhere. That stuff is just packing materiel and it should stay that way, stick to finding extruded foam sheets if packing grade EPS is all you have available.

FYI

Layne Rossi CAR S767 L2

substantial

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Reply to
L & K

Huh. I've got some of the insulation grade foam, and I hadn't realized that there was that much of a difference in strength or density between that and the packing-style foam. Thanks for the info... (of course, there's quite a large variety of foams used in packing. Some extremely light and weak, as comes in assemble-yourself furniture. Other quite a bit stronger, like the coolers they ship frozen food (and dry ice) in.) (I assume that the weaker, lighter stuff would be OK up to a certain size, though? I have this substantial collection of packing foam saved BECAUSE of it's low density, aimed at small model rockets and such...)

BillW

Reply to
Bill Westfield

Hey bill you got it. I actually produce the eps coolers you mention. You would be hard pressed to find anything that is stronger by weight. Our boxes test out at a breaking strength of 360 Kpa (about 52 psi) minimum. I've not found any other manufacturers boxes that test that high. I'm not bragging but if you find a packing box (from fish usually) made by NOBOCO or Aqua-Pak in Canada you will have some good material. I know there's a lot of it in the western states especially Kalipornia because our customers ship about

2000 containers of fish a day down there. The Quad-lock/construction grade eps panels are stronger but as I noted they are heavier. I used some for the core of a 4" nose cone.

Layne

Reply to
L & K

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