Monday, January 31, 2011

Snowtrooper: Third step (Part two)

When Yoki talked me in to our Snowtrooper project, she stated that it would be easy, because there is only a few pieces of armor in the costume. Bhah, I say! After some research I confronted Yoki with some drafts and showed her how many there actually were. I have never seen such an impression on Yoki's face, this is actually pretty describing (o.o).

We chose to do the armor parts from PETG plastic using vacuumforming method. The positive, master molds were made of insulation foam and wood putty. You can find the posts dealing with the clothes, equipment preparations and references behind the links.

Third step: Production- Hard components

Our mold making started from sheets of insulation foam. We estimated the approximate measurements based on reference pictures and information. One of our reference sources was site dedicated to Snowtrooper construction, which provided measurements for male size armor. We scaled the measurements down comparing them to our size and portion. When the dimensions of the armor pieces were concluded, the foam was cut to proper sized pieces, stacked and glued with Erikeeper. We cut the rough form after the glue had dried with thin bladed saw or a carpet knife and started sanding. We used different rakes; the final sanding was made with the finest one of course.

For detailing we used craft foam, plaster or foam covered with putty, like the molds themselves. After the piece was completed, we added first layer of putty and sanded it smooth. This step we repeated few times, exposed foam had to be covered, because it would collapse under the hot plastic. We used wood putty because it didn’t smell and could be safely handled. Probably any type of putty will do, but do not use car filler, it will melt the foam. After the surface has been polished with finest grain paper Yoki varnished the molds three times before we went on to vacuumforming. We thought that the varnish would make the removal of the mold from the plastic copy easier. We also used silicon lubricant for that task.

Before vacuumforming we checked how many parts we can make with one sheet of plastic, maximum amount was two. We took notice that the pieces should be somewhat the same height. Big differences on height stretch the plastic unevenly and tears it. We used special, three way bolts as raising pieces. When they were placed under the molds the suction was enabled from every side of the mold. This also helps to avoid the folding on the hot plastic. For us folds formed with strict corners. Sometimes any trick worked, even; they happened never the less. The trick is to try to get them where they show the least.

We had custom made frames and platform for vacuumforming. There are instructions on the internet how to make a vacuumforming studio in home environment. We used regular vacuum cleaner for the suction and a normal stove. Bigger the oven you have the bigger parts you can form. Because the breastplate is rather big, we had to divide it in four different pieces. We did try to make it as a whole, but after five ruined attempts I cried a little and went on and sliced up the mold. If anyone needs unique flowerpots from clear plastic, resembling strangely Snowtrooper breastplate, but with folds and holes, let me know.

Abdomen plate plastication. Please note my pretty hairband.

The vacuumforming is rather quick, but taking the mold out from its plastic pocket and cutting the excess parts out is more time consuming. For cutting we used carpet knife and wore work gloves to avoid bleeding fingers. No joking. Keep your fingers safe, you need them if you'd like to continue making costumes. The other time-eaters were construction the breast plate and building two back packs. The gluing took time with the breast plate and the backpacks were made like the molds, but instead of varnish the surface was finished with glue. We didn't vacuum form them, because then the mold would've been in thousand pieces. I figured that it was easier to do them by crafting.

We painted the pieces with shiny white spray paint. Details were added by painting free hand or with stencils. Please note my ergonomic wposture and Yoki's protective gear aka Smurf hat.

Like the backpacks we made the thermal detonator holders from scratch. The inside is made from insulation foam and covered with craft foam, which is sealed with glue. The ends are insulation foam with putty and three coats of glue. I bended left over aluminum sheets for fastenings and attached them to the holder. Raised details were done from craft foam and sealed with glue before painting.

Velcro on the shoulder parts and breast plate construction.

Different kinds of methods were used to fasten the armors: straps, screws, buckles and Velcro. Assembling the armor will be the subject of my last making of post on Snowtroopers.


  1. Holy... O.O

    Wow. Seriously, that looks so good! Can you buy that PETG plastic from any hardware store, or is it more difficult to get? I almost feel tempted to try something like this myself someday, looks so cool! Can't wait for the final costumes!

  2. I'm not sure. I bought the plastic directly from the company providing it. Some bigger Etola's might have PETG in stock, because they are partners with Foiltek.

    PETG is not the only choice for vacuumforming. Many troopers use ABS and if I got the material right, I've seen cosplayers to vaccu styrene also!

    And thank you! Good luck with your costumes too!