Step 3: Making the skull cap

The most challenging part of the whole process was thermoforming and gluing the half-spherical skull-cap part of the helm. This doesn't mean it is particularly hard to accomplish, it just took the most revisions to get right out of all the other steps. Don't be afraid to cut pieces of foam larger than they need to be. This may be common sense for some, but it can be easy to overlook. Remember that I am also simply restating what I did to produce the helm pictured in the first step, and there are probably plenty of alternative methods to producing similar results, so don't be afraid to experiment.

First, I made a foam band with consistent 1" thickness. It's easiest to simply cut a strip off the edge of one of the thick EVA floor pads (and carefully removing the puzzle pieces at the edge). The more accurate, the better. Wrap the strip around the circumference of the cardboard tube, mark the intersection of the foam, and cut the excess off. Then wrap the foam back around and hot glue the edges together so the band fits snugly onto the tube. Tip: Add hot glue to both sides quickly, then press together. Gluing both sides of the foam makes the bond much stronger.

The top of the band will be glued to other pieces of foam, so it's best to leave the worse-looking side up and leave the cleaner edge down where it may improve the helm's final appearance. The band I made has two glue seams, as can be seen below. This isn't ideal, but I made it work by evenly spacing them out in reference to the glue seams on the rest of the skull cap. This is important because you will need to cover the seams with other pieces of foam, and by evenly spacing these out they can be strategically covered by thin foam that looks like trim rather than a randomly placed piece of foam.

Secondly, I cut pieces of the dome out into quarters. I had bad luck attempting to thermoform pieces any bigger than this, so this is the largest I will recommend if you're using my method. Using a measuring tape, measure a quarter of the circumference of your cardboard tube. This distance should be roughly the same as the arc length from the top edge of the tube to the center of the half-spherical frame. Add at least 2-3 inches to your measurement, and cut out a foam square with that dimension. The more you add to it, the easier it is to form.

Thermoforming the foam is pretty straight forward, but you must take caution to avoid injuring yourself and burning the foam. I was able to thermoform my foam by preheating my oven to 350, putting the foam piece on the center rack, and allowing it to sit for around 10 - 15 seconds. The foam should be very pliable, but not smoking heavily. I wasn't able to avoid producing a little white smoke, so make sure you have a ventilation fan going above the oven if it happens and avoid breathing any smoke.

Quickly remove the foam from the oven ( I was able to touch it with bare hands, but it would be smart to have an oven mitt handy) and drape it over three of the semi-circular cardboard frame pieces, textured-side down . Press down on the foam at the top firmly, and press against the bottom edge to try to form a consistent circular part. Hold the foam stable for around a minute, and blow on it to help cool it off. This may take a couple of tries, but if you get one wrong, you can usually re-heat it and form it again or do touch-ups with a heat gun.

Using the cardboard imprints on the underside of the foam piece, draw an outline as shown in the image above, and carefully cut it out with a hot knife or sharp hobby knife.

Repeat three more times to make four quarters of your half-sphere. Place them all over the frame with the band to check the alignment and see if any additional trimming or forming needs to happen before gluing. When satisfied, glue them together with hot glue, while keeping them on the frame but avoid gluing the foam to the cardboard frame itself. Start by gluing your first piece to the top of the foam band, and glue small sections at a time until you glue the entire piece down. Using this method of slowly gluing small portions of the foam together, continue the process with the rest of the pieces until you end up with a finished skull cap as pictured.
Can you send a link or photo of the heat gun? What about a hair dryer? I have a heat gun for heat embossing, will that work?
<p>So what is the shape of the quarter panel that you used for the dome? I've been trying to figure it out all day and I've use so many sheets of paper trying to get it right before using my craft foam/eva foam... :/</p>
Super helpful!! I've been making iron man parts out of random materials for sometime and getting frustrated with weird unexpected &quot;off-material/brand&quot; problems. This saved me from all that!
<p>Dude this is awesome! I am gonna have to try and make something like this, your tutorial will definitely help and I am going to look at the cosplay forum. I am thinking of using EVA foam because thats what everyone has recomeended, have you ordered from univfoam.com before, I found some there and it seems like a good deal.</p>
My project was a success because of your post and I wanted to let you know that. :) Keep posting, I would like to see what you can come up with. I recommend a wagon and horse prop or maybe a building prop so we can learn how to make scenes. The more reusable, the better. I spray painted mine and let the fumes wear off on a nice day then I sealed it. It was dry within the next 2 hours (roughly) and then I put a clear sealant on top of my metallic paint to make it resemble the looks of metal even more.
Awesome! I'm really happy to hear that. I dropped the ball on getting a lot of these projects done when I moved from college to a full-time job, but hopefully I'll be able to get some more instructables posted some time in the near future. Thanks for taking the time to let me know; it's encouraging to hear that my work has inspired others.
I wanted to say thank you for posting this-- I've made my own armor with it! &lt;3 <br>http://imageshack.us/photo/my-images/571/dsc0750j.jpg/
Sweet job. I have made a pretty nice papier mache helm, but I think I am going to try an EVA foam one to see how those results go. I am hoping the foam will create a little smoother to work with initially.
Where did you get the horns? I was planning to make a sinister viking type helmet with similar horns but have no idea where to find them.
very nice!
Fantastic instructable!
i used to wear a helmet like that, but then i took an arrow to the knee!
Not the heel, Mr. Achiles?
.........KRII LUN AUS!
EVA foam is easily one of the best costume making materials!
Did anyone figure out where to get the card board peice he found in the trash?
It is a sonotube. You can get one at any home improvement place. It is used as a form for concrete poured-in-place pillars.
Dude, this is sweet. I am totally going to make one or two of these.<br><br><br>FUS RO DAH!
Is this airsoft proof
Just wanted to add my two cents when working with Mod Podge :3 <br> <br>I make gryphon costumes for kicks and the beaks are made in a similar way as your helm. I apply Mod Podge full strength over the papier mache beak forms and smooth it with my hands. Once your base coat is on thick enough to even out most of the bumps you can smooth it down even further by waiting until your most recent layer of podge is tacky and going over it with wet fingertips. In my experience I find glue takes too many coats and since Mod Podge is a sealer in itself don't prime my base forms with anything else first. <br> <br>I'll be trying this with EVA foam shortly; I've always wanted a warcraft Paladin's tier 2 armor despite never actually having played one :P Thanks for the ideas!
No problem! Thanks for the input, I'm always happy to learn new ways of doing things
Oh wow, this is great! I can't wait to see your body armor tutorial, I have a set that I want to make that I think your technique looks PERFECT for! I've little experience with prop armor, so I'm always excited when I see something promising. :)
Thank you! The body armor itself is still in the works, so the instructable is going to be a while, but so far I've used the same basic steps to make the armor with only a few additional techniques. So it may be easier to get started with some experience working with the foam in the helm project
I'll definitely give it a shot! I'd really like to do Lavitz's armor, from Legend of Dragoon; this stuff, if you're unfamiliar with it: http://media.photobucket.com/image/lavitz/waterworld119/LavitzModel.jpg<br><br> Does it look like a reasonable, simple set to start with? I don't want to start too complex and end up getting frustrated.
The scale looks reasonable and I think the armor itself doesn't look too intricate. It probably will be a good project to begin with, but if I were you I'd start with some smaller pieces of the set and work your way up. If you're like me, you'll waste a fair amount of foam before you get it to look right, but planning and designing patterns to cut out is probably the best thing you can do to reduce your consumption of foam and speed up the building process. Good luck! Hopefully I'll have enough time to finish my set of armor and can post another instructable in a reasonable amount of time. Until then, here are a couple of cool inspiring videos that might give you more ideas and techniques to work with:<br><br>http://www.youtube.com/watch?v=vb6CXGortrQ&amp;feature=results_main&amp;playnext=1&amp;list=PL412F405522C66539<br><br>http://www.youtube.com/watch?v=_S0zGnNVtxk
hardware stores sell thick cardboard tubes that are used for cement forms.
I haven't had luck finding them at hardware stores in my area, but that's good to know! Thanks for posting
this is really cool. great instructable.
You've shared some great techniques here. Thank you!

About This Instructable


395 favorites


Bio: I'm an aerospace design engineer with a degree in plastics engineering, and interested in doing cool stuff. I love building things and problem solving ... More »
More by SyntheticChelovjek: EVA Foam Armor - Helm
Add instructable to: