Big props to Jtm for the amazing original model!
For this remix, I split the original mask into 8 parts for printing on a small 3d printer with a 200mm x 200mm x 200mm build volume. The model is at the original size and fits my adult male very large head with a bit of room for padding. I printed in PLA, plastic welded the parts together with a soldering iron, sanded, primed with filler primer, then painted flat black and did the chrome areas with Testor's model paints.
Check out this amazing video by Lethal Engineering showing the process of making the mask: https://youtu.be/q4SUf6u8SyU
I printed with skirts so the parts would stick to the bed better. Minimal support is needed, depending on your printer. But you DON'T need a huge amount of support for the big curved parts of the mask when printing in PLA with good cooling. It's a little nerve-wracking to watch, though!
Be sure to flip the parts around so a perfectly flat side is the bottom of your print.
I used this voice changer, hot-glued to the inside of the mask with the speaker on a necklace under my shirt. Worked great and really added a lot of polish to the costume: http://amzn.to/2fxu6ej
Taped up to make sure things were generally working
All the parts fit together. Why was I surprised?
Plastic welding using a flat tip on this soldering iron. Worked surprisingly well, inside and out. Outside seams sanded down well.
Used Loctite putty to fill gaps. Most anything would have worked well, even drywall patch stuff. Sanded down after with an electric sander. At this point I should have added some of the
Primed with filling primer, 3 coats
Painted with flat black.
Chrome added with Testor's model paints. Took about 30-40 minutes.