Looking for a suitable skin for foam

[skupilkinson]

Hi guys and gals,

I'm in the UK, and I'm looking for a suitable medium for skinning styrofoam models. Aves isn't readily available here, I used Milliput once but it wasn't the easiest to work with over a large area and reguired a lot of extra anding.

I tried rolling it out and even thinning it with water into a paste for spreading but with no good results.

Is there something I can get here in the UK, that can be spread over large surfaces like plaster only stronger? Maybe something from car body shops?

Also, if there is something available out there that won't melt the foam, can it be scribed?

Thanks in advance, hope someone can help.

[tonyG2]

Well I was going to say milliput but you've already tried it.

Most car body repair putties that I know of will dissolve foam.

It may be worth trying something like Tetrion. Its generally harder that the usual plaster. That said, I don't know how well it takes to scribing.

Weaker - but still an option - is papier mache. Used with a permanent wallpaper adhesive it will be fairly hard (not as hard as milliput) but will need some sort of sealent when its done. There used to be a Humbrol dope that you could apply to balsa etc which built up to a hard shell. That might be used on top of the papier mache mix.

[skupilkinson]

Thanks for that. Would epoxy resin be suitable? The type used for laminating and coating? Maybe something that could just be painted on and sanded smooth.

I'm not against using milliput again, it is tough whe set. I'm just trying to look into alternatives.

[max142]

I use bondo to cover stryrofoam. It will set up before desolving foam and leave a hard shell. Try on scrap piece of foam to see.
Then I cover with bondo glaze and sand back.

Spread the bondo filler in patches for it sets up quickly and don't try to spread once it starts curing...better to wait till cured then sand back. After drying( about an hour or so) sand smooth , then cover with glaze. let dry then sand again.

It will make a good hard and smooth surface.It's also cheap.

[skupilkinson]

Cheap is good. Always.

So what happens to the foam? Does the foam continue to melt after the Bondo has cured? Or is it safe underneath the bondo. You hear about some paints on vinyl figure kits being applied and everything seems ok, later sometimes as long as years later, the vinyl breaks down.

Also, is Bondo a brand name? Is it avaulable here in the UK? I'll look into that.

[max142]

the model remains quite strong. And Bondo is a brand name. Cheak at local DIY centers or auto stores. Walmart, if there, is a good source.

[skupilkinson]

I've been phoning around. No joy, Bondo is an american product and not available here in the UK. One guy hadn't even heard of it.

Does anyone know of british or UK available proucts that are just like Bondo?

[tonyG2]

So far as I know Bondo - at least under that name - isn't available in the UK.

I tried using Davies epoxy resin once and it did leave voids under the surface when it melted the foam.

I've looked up Bondo equivalents

According to MP3Car.com Isopon P38 and Isopon P40 from Halfords are the equivalent of Bondo. Assuming you belive what you read in forums

http://www.mp3car.com/vbulletin/fabrica ... alent.html

[skupilkinson]

I was afraid of someone saying that. Bar did a test the other night for me as he already had Isopon P38 in his garage. When he went to check on it the stuff was bubbling!! No good.

Halfords has "Locktite Porfessional Bodyfiller" but I don't know how it'd work.

I'm asking here before trying anything. Makes sense rally someone may know of an alternative.

[skupilkinson]

Well that thread was brief. Maybe it has the same qualities on car body work, but not when it comes to styrofoam??

Would Bondo be expensive to get shipped to the UK? I'll look into that later.

[modelnutz]

I coat standard housing foam ( polystyrene or EPS ) with Smooth-On's sc-300 fast cure urethane...works really well...it cures to a sandable finish in 15 min. or so.....you can mix and paint it on with a foam brush doing small areas at a time...it bonds to it's self really well. I have also used it with fiberglass as a substitute for polyester resin...slower stuff works a bit better for this app though.

Best part is...it does not attack the foam at all !

I'd bet that any urethane would work just as well.

If you can get some urethane, give it a try...I think you'll be pleased with the results.

Modelnutz
"the name sez it all"

[skupilkinson]

Thanks, sounds promising.

So I just ask for "Urethane"?

[Umi_Ryuzuki]

Depending on what you are doing, there are a few ways to do this.

1. cover the foam with duct tape, and go to town with polyester resin
2. paint the foam with several coats latex paint, an then use polyester or epoxy resin.

3. paper mache' over the foam and use polyester, or epoxy resin.

4. Just use epoxy resins on the foam.

I used epoxy resin and fiberglass, here, on the SDM tug hull.

[skupilkinson]

Yeah, I mentioned using a resin earlier as I can get that easily. So to use it I basically just need to seal the foam? Would PVA be suitable? Just paint on, dry, and go to town with the resin?

That suits me down to the ground.

[Umi_Ryuzuki]

I don't know how PVA will hold up. Also, PVA would not allow any adhesion to the foam structure.

You should be able to find an Epoxy resin for fiberglassing.
That should resolve all the foam disolving issues.

Polyurethane resin would work(be safe for foam) also, but I have never used it in such a manner.

[TER-OR]

I've had great luck rolling Aves epoxy putty out very thin using cornstarch as lubricant. Miliput may be too stiff to do it right.

[skupilkinson]

Thanks for that, I'm thinking of going down the Aves road, but I was really hoping to find something here in the UK that I can just pop out and get easily when I run out.

[Lt. Z0mBe]

If you use Bondo equivalent, use the Bondo spot filler in the tube, NOT NOT NOT NOT NOT NOT NOT NOT NOT NOT NOT NOT NOT the two part kind. IT will destroy the foam.

OTherwise, try ordering Aves from the store here.

I hope this helps.

Kenny

[TER-OR]

A&B Putty also works well. I'm not sure if it's available in Europe.

[skupilkinson]

Well, I've been looking into this over the last week.

Antenociti's Workshop is a place where I usually get my foam. It's based in the UK, which is a plus for me. I've been chatting with Jed, the owner and he's informed me that he'll be stocking Aves products in the next week or so.

So, good news really. Just hope he chooses to stock the paste.

[TER-OR]

I wouldn't try to use the paste for this project. The Putty can be rolled thin and used to skin the foam. The paste you'd have to sand smooth.

Get a polypropylene rolling pin and some corn starch. the rolling pin can be found at places which sell confectionary supplies.