Ever since I saw the Rocketeer when it first came out, I've wanted a Rocketeer costume. Recently, I decided it was about time that I had one. Now, I could have bought a helmet kit and painted/detailed it, sure - but I love a challenge, and half the fun is building the thing, so I decided to go all-in and build mine from scratch.
The plan is to sculpt the main part of the helmet in clay, and then slush-cast it in resin, and then put a layer of fiberglas inside for extra strength. I'll likely build the fin using some technique that makes it more durable than a resin fin might be (my fear is turning my head and whacking the back end of the fin on something, breaking it off).
So, to start the process off, I built a cardboard version of the helmet to try and judge how big the thing would be, and to have a little fun. I didn't use any kind of pattern, just some photo reference and making it up as I went along.
The cardboard version ended up being obviously too large, but it was fun to build and my daughter loved it.
UPDATE, 6-12-13: I junked the first try that's detailed in the next few entries and started over again, so unless you just want to see what I did wrong, you might want to skip down a bit.
UPDATE, 6-22-13: The second try was a fail as well. Third try coming up...
UPDATE, 7-1-13: Third try under way, using Monster Clay.
UPDATE, 10-12-13: Complete! This is a long thread, with many twists and turns and false starts and re-do's, but it all works out in the end. Here's what the final product looks like: