Starting my pepakura deathstroke helmet Stage 1:Download pepakura Viewer.It is free but you can buy a better version pepakura designer but that costs.I use pepakura viewer.Then print the shape templates out.
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Iconic Helmets Infographic http://geekxgirls.com/article.php?ID=6028
My Halo 3 CQB helmet, hand built from a pepakura file.
Gallery : Pepakura Designer
Pepakura Designer - papercraft
3D Models for Pepakura Designer
Red Hood Helmet by IdiotsArmory on Etsy
Cardboard Helmets by Zygote Brown Designs| Viking Helmet | Roman Helmet