This helmet was first featured in Star Wars - Return of the Jedi and was worn by the six guards that accompanied the Emperor. At the beginning of this project, I could not find schematics to define the geometry of this helmet, so I had to rely on images gathered for the internet and referencing screen shots of the films. Once the geometry was defined in 3D modeling, the master was built and the mold created. The castings are rotocasted urethane epoxy resin with red pigment and clear coated with polyurethane. The visors are 1/8" thick smoked acrylic that are thermoformed.
This 3D model was created based off film screen shots, images from the web, and measurements from my first customer. The layers are separated by 2 1/4 inches and represent layers of 1/4" MDF that would be filled with 2" insulation foam and carved to shape.
I got the idea of using rigid layers filled with foam from the way they built the model of the USS Enterprise for Star Trek The Next Generation. The layers were printed out, placed on sheets of 1/4" MDF, cut out and assembled. Insulation foam was used to fill the 2" voids between layers and shaved down to shape. Bondo was used to create a hard shell over the foam. The bondo was sanded down and coated with filler primer and then automotive primer. The automotive was sanded with a 600 grit sanding sponge. At this point, the mold was ready to be made.
The mold consists of two parts; a rubber glove mold and a two part support mother mold. The rubber glove mold is made of Smooth-On's Mold Max 30. Thi-Vex and Fast Cat 30 were used at different points to either thicken the rubber or increase the curing rate. The support shell was made of Smooth-On's Plasti-Paste. For detailed instructions of this molding process, check out this video.
Casting and Finishing
The final products were rotocasted using Polytek's EasyFlo 120 rotocastable urethane epoxy resin. The plastic was dyed using Polytek's Red PolyColor Dye. The castings were trimmed with a rotary tool and coated with Minwax's fast drying polyurethane gloss clear coat. The visors were thermoformed out of 1/8" smoked acrylic and superglued into place.