This is a bit of an impromptu instructable, so I may not have perfect pictures so bear with me and I hope you enjoy it.
Step 1: Materials/ Tools
Thin steel (not exactly sure what thickness it is as I did it quite a while ago)
Anvil (steel block works fine)
Step 2: Marking and Cutting
First step is to mark out the main 2 shapes which should be about the size of your profile. Then mark the center strip which will run down the middle of the helmet connecting the two halves. Then using the tin snips cut out all the shapes.
Step 3: Molding
This step is probably the most tedious. Hammer the halves into shape in order to best fit your face.
*side note: this may seem obvious but make sure not to curve them in the same directions so that you have 2 lefts or rights
Step 4: Fitting
Make slits about 2 inches apart and 1.5 inches deep. Then start to hammer and bend the edges in order to curve them the better fit your face. They don't need to come full circle to each other because of the center piece.
I apologize I didn't take any pictures of the center piece. It needs to be wide enough to connect the side in order to fit your head best, also it must be just as ling as the perimeter of the sides after they are curved.
(Optional) Once you finish shaping the mask, hammer inward to create the indented cheekbones on the lines from step 2.
Step 5: Assembly
Before you connect the three pieces, cut the eye holes (which can be in any shape you want) and make sure they will compliment each other when the pieces are connected.
To connect them drill holes that line up on each side then rivet them together, but make sure to measure along the way to make sure your head will still fit. Otherwise you could make on mistake or slip and have a helmet fit for a 3 year old.
Step 6: Paint
In order to paint just the center (as I did on mine) , apply painters tape to the sides and spray the center. I chose purple because that was the best color I had at the time, but I would have preferred black. And of course the sides would look good painted as well.
Step 7: Finished
Once your done you could add whatever goggles you want, I would suggest welding goggles or you can leave it bare, which also looks good. If you leave it bare I would suggest adding dark plastic or cheap sunglasses lenses behind the eye sockets. If I get enough requests I may make an instructable showing how I made the welding goggles if I have the time.
If you enjoyed this instructable be sure to check out one I should be posting soon on one of my other steampunk masks.
Thank you for viewing and God Bless.