Introduction: Vacuum Forming Costume Armor

About: Artist, designer, director, fabricator & mentor in cinema arts & video games. 20 years professional experience employed on projects including Star Wars, Call of Duty, Jurassic World, Transformers etc. Freelanc…

In this tutorial I show the basics of the vacuum forming process for a piece of chest armor. "JAX", one of my 7th grade students wanted to make a character costume inspired by Hunters in the Destiny video game. Our design is not intended to be exact to any specific design in the game, only similar in concept to a lightweight Hunter / Scout style costume.

The above image is a Destiny reference image, property of Activision & Bungie.

All other images in this Instructable are created entirely by and property of FunPro & FPDesignFab.

Step 1: Make a Template

We used construction paper to design the shape and size of our chest & back armor, shin armor and shoulder armor. In this instructable I'll just cover making the chest armor piece.

Step 2: Build a "Plug"

Next we build a plug to vacuum form over. This plug is the shape of the armor. The plastic will be heated and formed over top of this piece. I used scrap wood to build this plug. First I made the center shape, think of it as the sternum or breastbone of the piece of armor. This center piece needed to have an angle to best fit the chest. Next I cut four individual pieces for the panels. I then beveled or angled all the edges of each part on a belt sander so they all fit together flush. I attached the armor parts to a flat platter using wood glue and a nail gun.

Make sure edges of the plug do not have undercuts. Every edge of the plug needs angles to be slightly obtuse, that's more than 90 degrees. The edges here are probably around 100-110 degrees. If the edges of the plug are acute, or less than 90 degrees the plastic will form around the plug and trap the plug inside the part. Ensure the plug will release from the formed part by using obtuse angles on all edges.

The final pass on the plug is to fill any gaps and smooth the seams with "Bondo" or other car auto body filler. After the Bondo dries sand the entire piece to make smooth.

Step 3: Vac Form

The plug goes into the machine on a pneumatic actuated platform. The plastic is clamped into the 24" x 24" frame then heated in the oven. When the plastic starts to melt and sag we slide it along the track until the framed plastic is over top of the plug. Next we raise the plug into the sheet of softened plastic then hit the vacuum switch which sucks all the air out and pulls the molten plastic tight to the shape of the armor plug. After it cools for a moment remove the plastic sheet and we have a piece of armor.

Step 4: Cut Out Part

First roughly cut off the excess edges on the part. Next use a marker to draw an even line for the final edge and cut out armor with a pair of snips.

Step 5: Paint and Detail

Paint the part then add some aging. For this piece we had limited time to finish the class and shoot some test photos of Jax in costume so we very quickly aged this part using a spray paint rattle can, a rag and a sanding block. On a longer term project we may have used acrylic paint and airbrush to do more detailed aging. We'll also add a stencil logo graphic to this armor in a later class.

Good aging basically starts with putting grime in the crevasses and scratching the raised edges. I showed Jax two techniques of how to spray paint then quickly smudge it with a rag to get different looks. Then we used a course sanding block to scratch the edges. Finally we attached the front and back armor to 2" webbing straps.

Step 6: Photoshoot "screen Test"

I quickly set up a light and shot a few test images of our work in progress on the Hunter Scout costume. This is currently where we're at with the armor on this character.

Step 7: Video

Watch a video of this vacuum forming process on my youtube channel here:

Step 8: Follow and Support Our Work

Check out more work on our sites below. If you like what you see consider supporting and sponsoring our work:

Sponsor our independent work on Patreon:

I have 4 years backlog of documented art, design & filmmaking fabrication projects that need to be made into videos and published. Your sponsorship and support helps make it happen! Every dollar per video helps make more videos, faster and better.

Subscribe to our newsletter:

Follow FPDesignFab on Instagram:

Watch & Subscribe to our videos on Youtube:


About me:

I'm Christopher Scott, a freelance artist. I work full time and then do this indie project work in my spare time to mentor and benefit my students who are learning art, design & fabrication for the entertainment industry. Your support and sponsorship will help deliver many more videos and instructables like the ones on this channel and on our Youtube channels.

I've worked professionally in feature films, video games and product design for over 20 years on projects including Jurassic World, Star Wars, Call of Duty, Transformers and Terminator to name a few. I'm a freelance artist, designer, director and teacher developing indie projects for Funpro school of cinema arts as well as performing regular work on professional jobs.