Craft FoamCraft foam is one of the best resources for costuming and prop making. You can pretty much make anything out of it, from crowns and jewelled collars to armor to shaped sleeves and jackets - the possibilities are astounding. Who knew that thin porous sheets of plastic foam were going to be a costumer's best friend?
Craft foam (also known as Foamies, Fun Foam, Kid Foam, etc) is usually found at craft stores like Michael's, Joann's, Hobby Lobby, and such. There are two sizes, a 2mm and a 6mm thick sheet in up to 12 X 18 inches. They come in lots of different colors, so it's easy to choose a color for your project. I generally use the 2mm sheets, but if I need a thicker section of foam, I'll either buy the 6mm sheets, or I'll glue several thin sheets on top of each other.
Since craft foam is fairly forgiving, I usually just cut it out with a normal pair of scissors. There are times when I need precise edges, so I'll resort to my Exacto knife. It's also very easy to score craft foam (i.e. make indentions in the foam) by using a ball point pen, a dull knife, or my favorite tool - a seam ripper. If you need to make raised designs on the foam, you can use Tulip fabric paint, Gem-tac jewel glue, rope or cording, rhinestones for rivets, wire, beads...again, the possibilities are endless.
Once you've cut everything out, you then need to glue it down. I personally use hot glue, but I hear that super glue also works very well. After it's all glued and secured, you can paint it! Now, there are differing methods on how to paint craft foam. Some say you have to seal it first by coating it with glue or a clear sealant, and some say just start painting. I'm of the mind that both of these methods work equally as well. I have done both, and I like to use each method for different purposes: Sealing foam for armor, and painting it straight on for smaller items. Each method requires several coats of paint regardless, so it all depends on how you want it to look.
Shaping craft foam is quite easy, as well. In order to get it to keep a rounded shape, you have to heat it. I personally love my heat gun, but you can also use a stove top burner, a hair dryer on high heat, or you can iron the foam. (A little side note, you can also iron the foam to seal the surface without coating it in glue!) As long as the foam is hot, you can shape it into rounded or curved shapes. And you can use just about anything for shaping a rounded or curved surface - a glass bottle, a bowl, a ball of some sort, a snow globe, a wig head, a duct tape dummy (this is the best for shaping armor!), a mason jar; or you can just shape it with your hands. Make sure you leave it on the form or in the shape you want until the foam cools completely, or it won't hold the shape. You may even have to do this several times in order to get your perfect shape.
Once you've shaped your foam, you need to reinforce it, or it will be flimsy. One coat of glue and a layer of fabric on the back of your prop will be enough to set the shape. The bigger the surface area of the foam, the more layers of glue and fabric you will need to keep a rigid shape.
In any event, just remember to be creative! You can make the most extraordinary things using the most ordinary materials (shameless plug for found items!).
Craft Foam Armor
This is the best tutorial I have found for making armor out of craft foam: http://entropyhouse.com/penwiper/costumes/helmsdeep.html
However, I have made some nice little discoveries on my own, as every person will, while using this tutorial. I followed Penwiper's craft foam armor tutorial pretty much to a tee. The heat gun works wonders. Plus, it's all very lightweight and sturdy to boot, which makes it even better to wear! I formed my armor to my body using a body dummy (that I cheaply made of duct tape - see this tutorial: Clone Yourself a Fitting Assistant ). For the fabric backing on my Eirika armor, I used 2 layers of muslin to get a more rigid form and lots of Tacky glue to coat the inside. A few layers of fabric feel a lot better than just one in my opinion. For my Alicia costume, I used two layers of brown wool/cotton for the backing and added a strip inside on the waistline for more reinforcement and it's very rigid. Just remember, the larger the surface area, the more fabric you'll need for support.
I did use the Rub-n-buff for the gold parts of each armor, but for the yellow armor for Eirika and the dark brown armor for Alicia, I used acrylic paint mixed with part of the glue/water mixture. This helps thin the paint out and still stay somewhat flexible when dry instead of cracking. When the glue dried, the paint color was left behind. I painted the color on in 2-3 coats after applying the 7-8 coats of water/glue, and then sealed it all with the Future Wax. I did experiment with different sealants and found Future Wax to be the best. Some people use Mod Podge, but it was really dull and it crinkled way too much to be effective. If you want a harder armor, consider polyurethaning the outside a few times instead of coating it with glue, then painting with a solid acrylic, then sealing (though I have not tried this with armor, I did make my Feena headgear solely out of foamies, then acrylic paint, then polyurethane, and they are pretty hard).
Once I was finished painting and sealing Alicia's armor, I applied a brown shoe polish to all the brown armor pieces and buffed it to give it a slightly leathery/worn look. I did use silver Rub 'n Buff for some of the metallic details, but I found a nice silver metallic acrylic paint (mixed with the glue/water) that was easier to use. The Rub 'n Buff needed 2 or 3 coats painted on by brush and buffed after every application to be really opaque and even in color, but the acrylic was fine with 1 or 2 coats and no buffing necessary.
Both sets of armor are actually quite hard and I have no worries about them tearing or breaking apart. All the armor pieces for Alicia are attached by buckles and straps, and Eirika's breastplate slides on via shoulder straps and the pauldrons are secured with wire hangers, which give them a raised appearance. So, again, be creative! I found out most of these details after trial and error, and after seeing what worked best and what didn't. Should you have any questions regarding your craft foam or foam armor needs, feel free to email me at firstname.lastname@example.org .