The Wonders of Wonderflex – Making Iron Man Armor



I’ve been having a great time with my new favorite material, Wonderflex! It is a thermoplastic sheet that you can cut with scissors and then heat and mold into shapes. When heated, it becomes sticky so you can stick it to itself or other materials. I’ll give you a demo on how I made some Iron Man armor to show a bit of what Wonderflex can do.

There are some amazing examples of cosplay Iron Man armor out there. But I wanted a very lightweight version that would work for running. You could probably do this with craft foam, but I wanted something sturdier with a more armor-like finish.

Once I came up with a concept drawing for my armor, I made a cardboard mock up. I like using corrugated cardboard for this, since it bends easily and I always have lots around. I found some cool color-changing lights at Jo-ann to use for the arc reactor. Then I scoured the hardware store until I found a drain cover that made the perfect “grill” for the light.


When I was happy with the cardboard mock up, I took it apart and used it for a pattern to cut out my Wonderflex. I also cut out craft foam pieces to use inside the Wonderflex to add thickness. When you cut out your Wonderflex pieces, you want to add about an extra half inch all around. The foam pieces are cut without the extra half inch, they are the finished size. This lets you seal the foam inside the Wonderflex. Be sure to save all the little bits of Wonderflex, because you can use them to do repairs or for adding small details.



Before I put the pieces together, I made forms out of Styrofoam (see my post on making Kevin’s head for more on this) to get the proper bend in the chest and shoulder pieces. You can’t form Wonderflex on your body, because once you heat it up, it is, well, hot. People use all sorts of items for forms, bottles work well. You just want something that can resist heat and will separate from the Wonderflex once it has cooled. Luckily, I don’t mind a mess since the Styrofoam gets everywhere. I covered the forms with duct tape so the hot Wonderflex wouldn’t stick.


The process of putting the pieces together is fairly easy. I took one piece of Wonderflex and heated it up with a heat gun until it became flexible. I put that on the form and then laid the craft foam piece on top. Then I heated the second piece of Wonderflex and put it on top, sandwiching the foam inside. I used a spoon to press down on the edges of the Wonderflex to make sure they were sealed. Once the piece had cooled a bit, I cut off the extra material around the foam, leaving about an eighth inch margin to maintain the seal. In the picture below, you can see that I added another strip of Wonderflex on each side to hold the buckle glides. That is one of the cool things about Wonderflex, you can add bits and reshape just by heating it up again.


When I had the pieces all sealed, it was time to paint. I used Krylon’s Fusion spray paint as it is great on plastic. I set up a big cardboard box outside to be my “spray booth” and did several light coats.


I made straps for the armor using gold stretch vinyl. I fastened them with Velcro. I wanted it to be adjustable for size, so I put Velcro down the length of each strap. I was very happy how it turned out. And it only weighs one pound! The photo below shows the back side of the armor with the straps attached.


I have the finished armor in my Etsy store. Click on the picture below to see my whole Iron Man Collection.


For more information on Wonderflex, check out:

Cosplay Supplies’ FAQ on Wonderflex.
Cosplay Supplies’ tutorial on Wonderflex.
Leko Hat Supply’s tutorial on Wonderflex.
A good YouTube tutorial, in German but subtitled.
An elaborate set of cosplay armor that also uses Friendly Plastic.
The Stylish Geek’s tutorial on making Wonderflex arm bands.