A Beginner’s Guide to EVA Foam for Costumes

EVA foam is a versatile material commonly used in creating costumes and props for cosplay. It’s lightweight, flexible, and can be shaped into complex forms, making it ideal for simulating armor, weaponry, and other intricate designs. When starting with EVA foam, you’re engaging with a process known as foamsmithing, which involves cutting, gluing, heat shaping, and finishing foam to bring your imaginative designs to life.

As you embark on your first cosplay project using EVA foam, you’ll need to familiarize yourself with the tools and techniques essential for working with this material. Basic tools like a sharp utility knife, heat gun, and various adhesives will become part of your crafting arsenal. Selecting the right thickness of foam for your project is crucial; thinner foams are perfect for details and simple armor, while thicker foams lend themselves to sturdier, more substantial pieces.

Before diving into construction, planning is key. Having a clear design or pattern to work from will save you time and resources. Whether you’re creating custom patterns or using premade ones, it’s important to measure and outline your pieces accurately. By following some straightforward principles, EVA foam can be molded into almost any shape you require, providing a durable and realistic appearance for your cosplay creations.

Part 1: What is EVA foam and how do you use it for cosplay?

EVA foam is a versatile tool that can be cut, glued, and shaped to create costume pieces. It’s most often used to create armor (such as breastplates, pauldrons, arm guards, etc.) and props (such as swords, axes, staffs, scythes, etc.). However, it can also be used for any number of pieces of your cosplay project, including hats, shoes, masks, jewelry, and more.

To create these costume pieces, you cut out the flat shapes in EVA foam, glue them together, and shape them using heat. It’s a pretty simple process, but it can take a little bit of practice to get right. I recommend checking out TNT Cosplay Supply on youtube for a playlist with many tutorials for using EVA foam as a beginner.

Part 2: Choosing the right supplies for your project

When you purchase EVA foam, it will come in long rolled-up sheets. You can get the material in different thicknesses ranging from about 2mm to 12mm. The thinnest sizes will be used to add intricate details to your costume or create add-ons. The 6mm-8mm sheets are typically best for creating sturdy armor that is still flexible enough to mold. The thickest pieces are more often used for props.

Craft foam, which you can commonly find as a kid’s crafting tool, is also a type of EVA foam that can be used for some simple armor elements (such as arm bracers).

Other supplies that you will need to work with EVA foam include:

• A pattern: You can purchase or create your own EVA foam pattern. Check out the Kamui Cosplay store for some patterns you can buy.
• Glue or adhesive: I recommend contact cement, but you can also use super glue or hot glue.
• A sharp razor: A box cutter or precision razor will work, but be sure to sharpen it regularly.
• A heatgun: This will be essential for shaping the EVA foam.
• Sandpaper or sanding tool: I like to use a Dremel, but regular old sandpaper is also an option.
• Primer and paint: Use whatever colors you need for your project.
• Attachments: Make sure to think about how the costume piece you’re making will attach to you and stay in place. Common attachments are velcro, snaps, elastic, hair clips, magnets, and zippers.

Part 3: Finding an EVA foam pattern

To get started, you’re going to need to work with a pattern. You can either purchase a pattern online or create one yourself. One of the best places I’ve found for pre-made EVA foam patterns is Kamui Cosplay. But there are also plenty of other places to purchase patterns too.

If you are dealing with a flat, or mostly flat, object, you can easily draw it out. Make sure to think about the measurements of the prop or costume piece so that you draw it at the correct size.

If you don’t want to buy a pattern or cannot find one that works for your costume, then you’ll have to make one. To make a pattern, you use a base object to copy. If you’re making an arm bracer, for example, you would use your forearm, or your torso if you’re making a breastplate. You can also use a pair of shoes as your base for foam boots, or create a new shape from scratch, such as horns, using aluminum foil. (some examples of what I mean: boots, horns, breastplate, helmet)

The TNT cosplay videos that I mentioned earlier do a good job at explaining this process:

• More tips on how to create your own custom EVA foam templates

Part 4: Mock-up your design

While not strictly necessary, I find it useful to mock-up my design before I start putting anything together. What I mean by this is putting your design together in paper before making it with EVA foam.

This is especially important if you created your own pattern because it will ensure that all of your pattern pieces really do fit together. This will also help you remember how everything goes together and prevent you from making any mistakes like gluing pieces in the wrong spots.

Part 5: Cutting your pattern pieces

First, trace the pattern pieces onto the EVA foam. Make sure to label all of your pieces and include the registration marks (these work like notches in sewing patterns). Then carefully start cutting out all the pattern pieces.

For clean cuts, you want to make sure you’re using a very sharp razor. It’s best to have a knife sharpener handy and regularly sharpen your razor blade every few slices so you don’t start to get ragged edges. The thicker the EVA foam, the more often you should sharpen your blade.

Part 6: Glue the pieces together

The next step is to glue all of your pieces together. I recommend using cement glue. You can also use super glue or hot glue if that’s what you have available. If you are going to be doing a lot of heat forming (in the next step), I don’t recommend using hot glue, since it will start to melt when you use a heatgun. 

If you choose to use contact cement, use these tips to help you get a strong hold:

1. Apply glue to the two pieces.
2. Let it dry for 5-10 minutes until the glue becomes tacky.
3. Line up the edges of the two pieces.
4. Slowly push the two sides together, lining up the registration marks as you go.
5. Continue until you have attached all of the pieces.

Part 7: Sanding EVA foam

Important: When sanding EVA foam, use goggles and a face mask to avoid inhaling dust or getting it in your eyes.

Once all of your pieces are put together, it’s time to clean up the edges and seams. I recommend using a rotary sanding tool. This will make the process much faster than sanding by hand. You can, of course, still choose to use plain old sandpaper if that’s what you have available.

Dremel is the most well-known brand for sanding EVA foam in the cosplay world. I use a Dremel Lite for this step since it’s a bit cheaper and more portable than the original Dremel model.

Tips for using a rotary sanding tool:

1. Practice on a spare piece of foam.
2. Move the Dremel in the direction it’s spinning. It should be moving away from you if you’re right-handed and moving toward you if you are left-handed.
3. Go over all the edges and seams to create a smooth prop surface.

Part 8: Heat shaping and sealing EVA foam

Important: EVA foam releases mildly toxic fumes when heated. Be sure to stay in a well ventilated area.

The next step is to use heat. This has two purposes: to shape your EVA foam and to seal it for painting. For this step, you’ll be using a heatgun, so I recommend wearing a pair of work gloves to protect your hands.

Use these tips to shape the EVA foam:

1. Use a heatgun and wave it over the surface of your costume piece. 
2. Keep the heatgun about 6-12 inches away and shift the heat over the surface for a few minutes. 
3. Avoid overheating any spot on the foam for too long
4. Hold your foam pieces in your desired shape until it has cooled off (it will remain in the shape it cools in)
5. It can help to use an object to help hold the EVA foam in the correct shape. For example, use a wig head to hold a mask in the right shape while it cools

Sometimes heat shaping the EVA foam can cause small holes at the seams of your prop. When this happens, you’ll want to use some kind of caulk to seal up the holes. I recommend using Kwik Seal caulk because this brand is also completely paintable.

Part 9: Using primer and paint

But before you get started with paint, you’ll need to use one or two layers of primer. Without it some of the paint will be absorbed into the foam surface, and you’ll have to use more layers of paint.

The best primer that I’ve used for EVA foam is called Flexbond. This is a product that remains flexible after it’s dry, making it ideal for flexible foam projects. You can also use products like Mod Podge too, since that’s more widely available. You’ll just want to avoid bending your prop or armor too much.

After your primer dries, it’s time for paint. You can use any kind of acrylic paint that will get you to the right color, but more flexible paints will typically have a cleaner finish. Brands that I’ve used and like are Liquitex and PlaidFX.

Part 10: Attaching EVA foam to a costume

If you were making a prop, such as a staff or a sword, then you’re finished! However, if you are making any kind of armor or costume piece that you need to wear, then you still need to add an attachment.

For armor, this will usually mean adding velcro strips or elastic so you can easily get in and out of it. Horns and masks can be attached using hair clips or headbands. You can also use magnets, zippers, string, elastic, or any other type of attachment that works with your costume piece.

Experimenting with complicated designs and effects

After you understand the basics, there is almost no end to what you can make with EVA foam. You can add intricate details to make unique prop designs and embellished armor for your favorite characters. 

You can experiment with different shapes and layers. You can try creating different effects using the Dremel. You can even play around with foam clay to create more organic shapes. The sky’s the limit, go out and experiment!