EVA foam 101: how to cut, shape, assemble and paint your foam pieces
Never worked with EVA foam before? (maybe you don't even know what I'm talking about) Want to make more elaborate costumes? But you don't know how to make your accessories or armor pieces? Feel like leveling up your skills?
Well, let's talk about it a bit.
Whether it's for cosplay or LARP, EVA foam is probably the most versatile and accessible material for creating armor, accessories, and props. And if you're already familiar with this material, I might not teach you much. But who knows? Sometimes you pick up little interesting tricks everywhere, right?
Table of contents
- What is EVA foam?
- Where to buy your EVA foam
- How to cut EVA foam
- How to shape your pieces
- How to glue your pieces
- Finishing touches
- How to paint EVA foam
What is EVA foam?
You might already have some at home. You know, those interlocking anti-fatigue mats with the puzzle-piece shape? Well, that's EVA foam. It's a really cool material for several reasons:
📌 It's super lightweight
📌 It's really easy to work with
📌 It's cheap
📌 It holds its shape well, but is flexible enough to create all kinds of forms
| To learn more about EVA foam and other useful materials for cosplay and LARP, I've also got an article on my 10 favorite materials to try. |
Where to buy your EVA foam
To buy your material, you've got 2 options: either go to a store, or order it online.
In store
If you're in a bit of a rush, chances are you'll want to go to a store. In that case, you've got a lot fewer choices. One easy-to-find option: anti-fatigue mats.
You can find them at most hardware stores, at Canadian Tire, Walmart... that kind of store.
The most common format is a pack of 4 squares, 2'x2' each. It's pretty much always ½" thick (10mm), no matter the brand.
Heads up: the foam isn't smooth on both sides (you'll get a texture on the back). That's not always a big deal, but if you want to glue several layers on top of each other, it's easier when it's smooth.
You can also buy EVA foam at Michael's. A small upgrade from the anti-fatigue mats: this EVA foam is smooth on both sides. That said, it's still a low-density foam, of somewhat average quality.
For adding details, patterns, or texture, you might want something thinner. Look for craft foam. It's like EVA foam, but in sheets about 2mm thick. It's usually sold in 8"x10" sheets, at craft stores.
With that, you've got enough to get started, run some tests, and experiment with your new material.
Online
Say you've got time to wait for shipping. You can order your foam from specialty shops.
The big advantage, besides the fact that all their EVA sheets are smooth on both sides, is that you get more choice in thickness and density. You'll be able to more easily buy large foam sheets in 2mm, 5mm, 8mm, or 10mm thicknesses.
And very often you'll be able to choose between low-density EVA foam (easier to shape, so better for curved pieces) and high-density EVA foam (more rigid, so better for accessories and large armor pieces).
And most of the time, you'll also find all sorts of other related products (primer, paint, etc.) to help you gear up.
My favorite online shop is Red Moon Cosplay Solutions. They're based in Edmonton. Which means (if you're also in Canada): no surprise exchange rate fees, customs charges, etc.
| And if you're looking for patterns and files specifically designed for EVA foam, I've also got my own EVA foam pattern collection in my shop. |
Now that you've got your material, you'll want to cut it, shape it, glue it, paint it…
How to cut EVA foam
Personally, I use an x-acto knife. I've got a whole set, but the 2 sizes I use most are the big heavy-duty one and the small fine scalpel.
Heads up: foam really chews through blades, hard. So if you don't want to burn through an absurd number of blades for nothing, it's best to have something to sharpen them and get more use out of them.
Personally, I use a knife-sharpening block. There are tons of options on the market, this is the one I have, and I like it*.
But you know, you can also use very fine sandpaper (like 600 to 1200 grit). That does the job just fine when you're starting out.
To sharpen your x-acto, just rub your blade at an angle (15 degrees) against your block. And do it on both sides.
By the way, thin foam (2mm) cuts really well with scissors. But it'll wear down the blades on your scissors. So I'd suggest using a somewhat cheap pair of scissors for this. Definitely don't use your fabric scissors. You'll regret it!
(Worth noting: you can sharpen scissors too. But the technique is more complex than for a simple blade like an x-acto, and personally, I just don't have the knack for it at all. I won't be much help there...)
How to shape your pieces
To shape your foam, you'll need a heat gun. Heating it softens it up a bit, which lets you shape it. You can curve and round it into whatever forms you need. This lets you create contoured shapes for armor pieces that need to follow the body, for example. It's especially useful for pauldrons, breastplates, and vambraces.
While you've got your heat gun in hand, take the opportunity to seal your foam. It's kind of like closing up the pores on the surface of your piece. It'll help your glue and paint adhere better.
How to glue your pieces
Here, you've got a few choices.
If you're just starting out and want to try things out, you can always use hot glue. I'm suggesting it because we all have some at home. That said, it's not my favorite glue for assembling EVA foam.
The most effective glue is contact cement. I really like Barge cement (you can order it online from Red Moon Cosplay Solutions). It's a really strong, really effective glue. But also fairly toxic. Make sure you've got good ventilation, a mask, and the whole kit when you use it.
For a less toxic option: Lepage's green contact cement used to work really well, but unfortunately it's been discontinued. I'm still on the hunt for a non-toxic replacement for Barge...
📌 One important note: remember when I mentioned sealing the surface of your foam? That applies to the edge too, if you're gluing pieces side by side.
Finishing touches
Now that the base of your piece is done, you might want to add a specific finish or some decoration. Sky's the limit. But to start, here are 2 important steps:
Sanding
Sanding is pretty much unavoidable when working with foam. The idea is to clean up cuts that might not have been perfect, smooth out edges, round off corners, adjust joints... that kind of thing. Some people do it by hand. Me, I definitely don't have the patience for that.
So let me introduce you to my best friend: the rotary tool. If you've heard people talking about a Dremel, that's this tool. Dremel is a brand name. I've got the Mastercraft version from Canadian Tire (cheaper, and it does the job just fine).
It takes a bit of practice to handle the tool well. But once you get the knack for it, you won't be able to live without it.
Psst! After sanding, don't forget to re-seal your foam.
Patching the joints
You might find that your foam joints aren't perfect and want them to look cleaner. In that case, I use Kwik Seal. It's a flexible, paintable caulk. There are probably other brands that work just as well, but I haven't tested a ton of them. This one works well.
I apply a bit along the joint, and smooth it out by running a wet (gloved) finger over it. It'll fill in your gaps and imperfections.
How to paint EVA foam
Now that your piece is well sealed, you can prime it, paint it, and protect it.
The important thing to remember is to use products that stay flexible. Some primers and paints can crack if the piece they're applied to gets bent or curved. And since one of the main traits of EVA foam is being flexible, your pieces will probably bend (at least a little) when you wear them. So you don't want your paint cracking at the first opportunity.
Priming EVA foam
For priming, whatever you choose, it's always good to apply several coats to really protect your foam and hide any imperfections.
I really like Plastidip. It's a rubber spray primer you can find at hardware stores. It gives a nice smooth, even finish. That said, you might find it gets pricey. And if you don't have a well-ventilated space, it's not a great idea (nobody likes toxic fumes, let's be honest).
In that case, Flexbond works well. It's a lot like white glue, but it stays flexible. You can order it online (I usually get mine from CosplaySupplies), and I've even seen it at Fabricville. What I like about Flexbond is that it always stays vaguely tacky, even once dry. That means your paint will adhere really well. And paint that adheres well is paint that chips less.
There are other primer options out there. Just keep in mind that your primer needs to be flexible to preserve the flexibility of the EVA foam.
Painting EVA foam
As for paint, I really like acrylic: it's available everywhere, in tons of colors, and it's not too expensive. But I also use my airbrush (and airbrush paints) and certain spray paints.
Lots of things work. When in doubt, don't be shy about testing stuff out. That said, don't do it directly on your costume. Test on a scrap piece of foam first (with the primer and everything, if you want a good sense of the adhesion, texture, and finish).
| If you want to dig deeper into painting, I've got an article on painting techniques (for fabric, but it adapts well to foam too!) |
Sealing EVA foam
Like with pretty much anything I paint, I always prefer to protect my EVA foam pieces. I most often use Rust-Oleum spray sealant. But there are honestly tons of options on the market.
Heads up: if you're using a paint for the first time, or a sealant you've never used before, do a small compatibility test. Sealant sometimes reacts with paint and does unexpected things. And there's nothing more frustrating than ruining a piece on the very last step of making it, right?
So if you want to avoid ending up curled in a ball in the corner of your workshop crying because your costume cracked, melted, or exploded... trust me, test your new products.
There you go! I hope this demystifies EVA foam a bit for you.
If it's a material that interests you, don't wait! Go get some materials, borrow any tools you're missing, and experiment. Start with something simple (like bracers or a short sword), just for fun. It'll give you a good feel for the material before you dive into a big project.
| If you're ready to dive into an EVA foam project, I've got several EVA foam patterns available for you. |
And if you want to stay in the loop on new releases, promos, and new articles to help with your creative projects, join The Harbour!
In the meantime,
Happy sewing! Happy crafting! 🤓✂🐙