Styrofoam - help and advice

[Jim R]

Hi all
I have used the blue Styrofoam a few times over the years. I bought it years ago from a place called 4D Model Shop. Now I would like to try using it again having seen various members here and some people on YouTube use it to great effect.

I Googled Styrofoam and after half an hour or so I'm totally confused. Is Styrofoam a generic term for a particular type of foam or does it refer to just one manufacturer's product? What does XPS foam and EPS foam mean? I have read about foam having different densities and/or hardness. Is insulation board Styrofoam? I could go on and on :thinking: :crying:

I am sure someone could give me an early Christmas pressie by explaining in layman's terms what is best for making walls/buildings etc in dios and where such can be bought.

Thanks
a Very Confused Jim

Also what sticks the stuff. I gather it just dissolved with some glues.

[spanner570]

Hi, Jim.
I can't answer the first part of your question, but if you want an instant sticky then UHU POR is great for sticking foam.

The other UHU glue I use is UHU general purpose. Just make sure you get the non solvent stuff. This is not instant and takes a short time to cure. It is also a lot cheaper than POR.

Neither dissolves the foam and both come in a yellow tube.

No doubt other members will post different adhesives, but I know these both work.

[AlanG]

What does XPS foam and EPS foam mean? I have read about foam having different densities and/or hardness. Is insulation board Styrofoam? I could go on and on :thinking: :crying:

Jim. Have a quick read of this thread. It'll help explain a few things


Foam/Polystyrene for building up embankments | Scale Models Forums (scale-models.co.uk)

[Mark1]

From what I gather xps is not as spongy as eps so probably makes carving/shaping a bit easier, a coat of pva as a primer seems to be the thing to do, I bought some a while back not used it yet but have watched many tutorials on y tube.

[Jim R]

Thanks guys :thumb2: That link Alan is very useful. UHU sounds good and cheap and easy to get - a winner on all fronts.
Jim

[JR]

Morning Jim .
It's very confusing to say the least.
All building foams including blue and pink form are made using using polystyrene resin.
There is only one foam board made using polyurethane, and that is Kappa Line ,sold by 4D model shop .
UHU standard is the glue as 570 mentions
, however Kappa Line needs the other version from UHU POR

[Peter Gillson]

I use some old insulation board which I recovered from a builders skip - easy to cut and glue using woodworking pva glue. No idea what the exact type is but it was free and works.

Peter

[scottie3158]

I use blue foam board and I can't remember where I got it. But the higher the density the better. I use a hot glue gun for large parts and PVA for smaller parts. It's a good idea to seal the surface when construction is finished with diluted PVA prior to painting and weathering.

[Jim R]

Thanks guys. It is rather confusing but there again it doesn't take much to confuse me. The wife's been doing it for years :thinking: :tongue-out3:
Happy Christmas
Jim

[Tim Marlow]

I’ve used this stuff Jim

https://www.amazon.co.uk/gp/product/B009A81MQO/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1

It engraves OK, but has a bit of a textured surface. Great for stonework though.

[rtfoe]

I'm just as curious as you Jim.

All my life I have been using discarded polystyrene foam packing used in electrical appliance packing. Also from IKEA flat packing. Not used the blue or pink ones and only just recently started using those from meat packing trays and those sandwiched between two paper cards.

They all seem to be made from different compounds and act differently to UHU All Purpose. So on the safe side I use a Japanese craft glue similar to UHU but not solvent based for Polyfoam. Joints are strengthened with inserted pins or toothpics.

All surfaces are covered with spackle or acrylic paint to prevent damage and for texture and sculpting. You have to seal it properly or else there will be tiny creatures boring holes and leaving white powder on your display. I don't believe it's biodegradable dust.

Cheers,
Richard

[spanner570]

Just to clarify my post and what seems to be a bit of confusion re. my use of UHU general purpose and their POR version.
I use UHU POR for foam board and polystyrene.
I also use the cheaper UHU General purpose, for the same application, BUT it has to be the non solvent based! Use the ordinary UHU G.P. and it melts polystyrene and the like in nothing flat....

[Jim R]

Hi Ron
Thanks. That confirms what I have read. The different UHU glues can easily be confused but as you say the solvent based one is useless for polystyrene of any sort.
Jim

[JR]

I've found some interesting points on the web about foam, it's make up and types.
These all come from polystyrene.



The original foamcore was created and marketed in 1957 by the Monsanto Company. Their original brand name for the material was: Fome-Cor.

Foamcore, aka foamboard, is lightweight, easily cut, and surprisingly strong. In it's most basic form you'll find three layers: An inner layer of polystyrene foam, bookended by two sheets of clavcoated paper or simply kraft paper. The surface paper is slightly acidic but you can find acid-free versions for archival photography.


Foam, without the -core, is another very common design material. There are three basic types that can be used for modeling: Pink, blue and yellow (or Balsa foam.) Pink and blue foam are similar, both made from expanded polystyrene—in fact this is how they are most often referred. Best known as Styrofoam (created by Dow Chemical), they are by far the most widely used. Polystyrene is probably the most common plastic used on the market, and it is also very slow to biodegrade, and so makes up one of the more unwelcome types of litter on this planet.
Extruded polystyrene is lightweight, durable and ideal for creating all kinds of design objects. It can be worked with a hot-wire cutter or saw, or even a simple x-acto knife. (Just make sure if you are doing a lot of cutting or sanding, to wear a fume-mask, because the fumes are toxic.) You can paint Styrofoam with acrylic or water-based paint, but avoid any solvent-based paint, as it will damage the foa

Styrofoam has a tightly formed closed-cell structure. "Closed-cell" simply means that that the gas forms discrete pockets bordered by the material (in open-cell foam the pockets are connected, like in a dish sponge, so they can be filled with whatever is around them, i.e., water). It's the closed-cell that makes this material so water resistant.

The only other type that is available is Kappa Line and that is made from polyurethane.
All the types that we use, be it blue , pink are closed cell and can be scribed.

[Jim R]

Thanks John.
That's interesting and has cleared up some queries I had. I thought you may know about the stuff both from you dio making and from your building background.
Jim