Low Expanding Foam Helmet Finished

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Low Expanding Foam Helmet

Well here is my work in progress.Ive printed ,cut,glued,taped,resined my Pepakura helmet then used low expanding foam to make a lightweight helmet.Problem is im not to sure what to do next.There are many steps i took to get to this point (good and bad)that i will fill in later.Ijust wanted yous to have a look and possably help me find a solution.The inside will be padding and material but the outside is pourous and needs to be coated and smoothed to accept paint.
here is a pic.
I'd be happy with that, but i've never done this before, and its only my 3rd day working on the armor so over time i guess i'll do better.

but great job so far, keep updating, I'm interested because I am carving my helmet out of styrofoam.

cheers! :dee:
be careful when painting that stuff!! Styrofoam, and almost all foams, melt if you hit them with areosole paints. Try a cbase coat with brushing it on, then spray.

Wouldn't want that to melt on ya :eek
I can suggest a few things, but since I'm not familiar with the type of foam you're using, I'd also suggest that you make a test blob to try things out on. First off, you could brush on epoxy (doesn't matter how fast it cures, just get the one that will be convenient for you). Brush it on with a brush you won't be wanting to use more than once; i.e. a piece of crap. You could also spray it with resin, use some kind of filler, or just use some acrylic paint. You can get anything like this at the craft store.
wow! thats looks really good.
will you be doing a tut? because that looks like a really good method.
keep up the good work! ;-)
edit: ok 1st you need to coat in resin or glue. something to make a layer beetween that and the paint.
then you need to sand that layer smooth.
you can then paint without melting your helmet.
hope that helps.
If its made of great stuff, I've had no problems with aerosol paint on that. Be sure to test it out on a small spot first though.
The foam used is Weather Shield low expanding foam,its very stiff in most places just some places where it didnt cure till i broke open the mold are quite pourous.Ive tried white glue,spackle and im testing paper mache glue with thin tissue ill keep yous posted.ive got all the process steps photographed just need text it up to a tutorial.i was hoping to be able to save the pepakura shell for more trials but i had to desroy it to remove the helmet.i should have sprayed it with foot powder before i foamed it i think it would have released allot better.
thanks for the input :hyper:
I remember seeing that stuff in the hardware store before, but I never would have thought to use it like that. That's really impressive, it certainly gives me some interesting ideas. Do you know how well it sands though?
Dude, this looks like another great method for homebrewed armor. Keeps us updated with the foam spray route...Im interested...
You will need to put on a barrier coat before paint this with enamels or putting any epoxy or resin on it. Use something like Gesso.. or acrylic paint brush on a layer , and then you can use those materials saftey without your helmet melting because of the solvents reacting with your foam...

Reinforce, sand and fill gaps, then paint...

Looks good.
Hey, heres a chance to the reap the benefits of my father being a plastics engineer for 35+ years.

Great stuff takes normal paint fine. Unlike polystyrene foam (that pink stuff you get at home depot in huge thick sheets in the most common foam) which enamels will eat away.

Want a simple solution to sealing foam? Go to WallyWorld and buy Krylon H2O paint. Its latex (plastic) and it wont interact with the petroleum in most extruded foams. I use it all the time, works as a beautiful sealer. Then you can paint just about anything over it.

General rule of thum, you can paint enamels over latex, but not the other way around.
Awesome, thanks for the heads up. Now, heres another question. About how rigid is this foam, possibly encased in resin ? Anywhere near fiberglass ? Or would it be maybe, say, half that, but also quite a bit lighter ?
Fiberglass gets its strength from the glass mat soaking up the resin and bonding with it. I have made a few prop items out of Great Stuff. If you cut off the "skin" that forms, you will find a lot of holes due to the way GS expands. Its a chemical reaction with air, any time you have a chemical reaction with air, you get bubbles. Ever make pancakes? LOL

If you can fill in the holes, use this stuff as a clear coat:


Do one side at a time, its sands beautifully, is strong and glass-smooth. R/C airplane guys use this stuff as finishing material, it looks gorgeous. A little experimenting first with how this stuff goes on and sets up is key before just rushing into your helmet.
Well see, I have the inside of my helmet fiberglassed, so I was contemplating how to get the detail in. I had thought about clay, because I'm going to make a mold, because a few of my friends want some helmets.

Anyway, I saw this thread this morning and Im contemplating using a layer on the outside of the helmet, using an xacto knife to cut out some of the major sections, then sand it a bit, and then put some sort of finish on it.
Have you ever molded/used silicone or urethane before?

You can use clay, not super sculpy or any pottery clay, use chavant or roma plastina, available at art supply stores. If you use chavant, you generally have a no sulfur clay, which wont interact with the molding rubber. If you use roma plastina (which I use) it has sulfer and will react pretty badly with the molding silicone, so you clear coat it with krylon clear coat.
Ive never molded before, but Ive been doing a ton of research lately using the google machine. Also my dad has been in the aviation business for over 30 years, and he knows a little bit about molding but, not anything really complicated.

What he had suggested to me is to, buy a half face motorcycle helmet. Then build the MC helmet and fiberglass it, detail it and whatever else I wanted to do to it, then, if your looking at the MC helm head on, cut it right down the center, and make molds for each half.

Then make sure the pieces would fit over the motorcycle helmet and then epoxy them to the helmet and smooth out the line down the center and paint it all up.

The reason behind the half face motorcycle helmet is because it would make for a great inside, and it would also be easy to have enough room for fans and what not. Since it would also be cut in half, it would be easy to install the LED's and whatever else.
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