I wanted a slightly decorated one, something just slightly different from the ones I'd seen. I might use this for a body painting at some stage, but made it to fit me for a change.
Check out this awesome instructable on a card helmet as well:
One of the very best I've seen using card as the basis, fantastic work. Had I found this earlier I might have used his dome template instead of constructing one from scratch. Grrr
Step 1: Getting Started
The basis for all my helmets is a card dome made to fit the wearer. This is reinforced with resin and then coated with car body filler and sanded smooth. It takes quite a bit of effort doing it this way, but it is cheap.
For tools and materials see my other 'ible on making an armour mask. Same basic principles and using the same set of materials and tools.
In this case however, the dome needs to be a smooth shell. I started with some old cut up cereal boxes for the basic card. I measured my head from just above the eyebrow, over the tops of my ears to get the correct dimension for the base. Mine came out to 23 inches. I cut two strips 12 1/4" inches long and 3/4" wide. This gave me a 3/4 inch overlap on each for gluing. The advantage of doing it this way is that the glue tabs will tend to create a slight oval rather than a circle which is exactly what we want for a helmet. Your head ain't round.
Once glued together, I cut some strips 3/4" wide to start to build the dome. By varying the length of the first strip you can vary the shape of the dome. How 'pointed' it is etc.
This dome must be smooth, so I joined the first strip to the circle we made using masking tape. The ends of the strip actually rest on the top of the circle. This is fiddly to do but will pay dividends later.
Note: As each stage dries, keep test fitting to make sure that it is still the correct size AND SHAPE for your head. You should be able to get a finger between your head and the inside of the circle.
Next cut the first two side strips. It is important that these are exactly the same length. These will form the first two side supports for the dome. If you measure and position the strips carefully, then you will get a concentric dome. If however, like me, you want to alter the shape of your dome, then by moving them relative to the circle you can force the first support strip to change it's shape. I wanted a softer curve at the front and a steeper one at the back. I set my second supports off centre (towards the rear) by about 4mm. This forces the crest of the dome towards the rear of the helmet. Join the two support strips with masking tape, again butting the ends of the card.
Next I cut 4 more strips of cereal box, and using the 'by eye' method (that means an educated guess), I joined each strip to the base circle then bent them in to the correct general shape. Holding them against the crown I marked them, and then cut them with a scalpel so that they were a good butting fit with the crown. I joined them with masking tape.
Now it gets really fiddly. I switched to a much thinner card, 160gsm printer card in fact. I cut three sheets of card into 3/4" strips and offered one up to the frame of the dome I had made. Again using the 'by eye' method I calculated the correct length to reach from the circle to the crown. Working on alternate sides of the circle I started adding in strips, only securing them with masking tape at the base. I then glued the top sections into the inside of the crown trying to bend them to follow the contours of the frame.
Once they had all dried I started adding in the final sets of strips buy gluing them onto the back sides of the strips already in place. Once the glue had set I used little strips of masking tape to fully secure the bases and the crowns of each one.
After two days of work, including all the drying times, I had a dome that was already pretty smooth and the correct shape. This will require far less filler later.
I did a test fit, then finally gave each and every joint line a fillet of glue using my finger. I then let it dry overnight.
Step 2: The Faceplate
I drew up one side template on some scrap paper, then simply traced through onto another piece of scrap paper. These were then cut out and using some spray mount I glued them to a piece of scrap show card I had laying around. Big Mistake. I should have used cereal packet board. the show card is nearly 1/8" thick and very strong. However it was difficult to cut requiring three passes with the scalpel.
Once cut out I glued and taped the joint down the middle of the face. I chose an angle using the 'by eye' method and made a small card fillet to strengthen the back.
Now the second problem with the show card. It wouldn't bend cleanly! I had to resort to steaming it over the kettle (a bit dangerous), and even then I got some ripples in the jowls of the faceplate - use cereal card in future .....
Once bent I temporarily fixed it in place with masking tape, and then made adjustments to get the fit I wanted. I made marks where it would finally go so that I could reposition it later.
Step 3: The Neck Guard and Back Plate
The front plate was glued and taped into place, then the back plate was offered up. I had miscalculated the length by 3/4" and that left some gaps. Luckily for me the two plates are in very slightly different planes of alignment so I used the gaps to take up the difference. The two plates were then glued, taped and clamped overnight to dry.
Once dry, I cut two little filler pieces from scrap and filled the gaps. The neck guard was then added using hot melt glue.
There is a small gap at the front of the helmet between the angle of the front plate and the dome. This was filled with a small piece of card and glued into place.
Finally a small fillet of glue was added round the filler piece and the joint of the backplate to smooth out the joints. The whole thing is now getting stronger and much more robust.
This completes the major construction work.
Step 4: Strengthening and Decoration
Once the main construction work is done, it's time to start to strengthen, waterproof and decorate the helmet.
Start by giving the inner surfaces a single good coat of resin. Let it cure completely. You can see the cup with the resin in prior to mixing in the hardener. I never try to use more than half a cup at a time, it cures too fast. Also use the very cheapest brushes you can find for resin application. Once the resin sets the brushes are useless. You can try and clean them with Acetone but this stuff is a noxious as the resin so beware.
The resin will soak into the fibres of the card, eventually the whole thing will become a super strong mass of resin. There is a shot of the cured inner surface and you can see where the resin has soaked in.
Next give the outer dome a good single coat of resin, DON'T resin the lower outer surfaces just yet.
Next, using a piece of paper, roughly draw out any surface decoration you want to use. Once you have the design you want, draw it out onto the card surface of you helmet using a pencil.
I added some card eyebrow ridges and some flowery designs which are piped on using 'no nails' type glue. Hot melt should work just as well. Next I added some piping work using some wire hot melted to the surface. This was finally beaded using no nails glue and left to dry.
Now give the outer surfaces a good single coat of resin and allow that to cure completely. Include a second coat on the dome. Once cured sand off any major drips and bumps.
Everything should now be nicely sealed in the resin and the whole thing should be pretty solid. It is also now waterproof.
Step 5: Finishing the Dome
Once the helmet is cured sufficiently it's time to complete the dome. Using car body filler (I use Isopon P38) start to fill the indentations in the dome. I do this by using the supplied plastic applicators and dragging the filler from the base to the crown of the dome. Continue to do this in thin layers using small amounts of filler at a time. Don't mix up too much or it will start to cure before you have applied it. Better to mix little and often than to throw the stuff away!
Once you have a fairly even first coating, let it dry and start to sand it back using wet and dry or similar abrasive. I have some on a sponge and this can be dampened to keep the abrasive moist. Start with a fairly rough grit, and then add more filler and a finer grade grit. Continue until the dome is smooth.
If you find you are starting to sand away the underlying card, stop. Add another thin coat of resin to re-harden the card, then begin the filling process again.
This is a VERY boring and thankless task, it took me two full days of filling and sanding to get anywhere near what I wanted. It will look better in the end, but be prepared for long mind numbing hours of sanding!
Now turn your attention to the main part of the helmet, fill in any small gaps and indentations with the filler and sand back until you are satisfied that the entire construction is smooth and ready for paint. I gave it a final thin coat of resin to fill any scratches, by this time I was bored stupid and decided that was enough!
This stage is very boring and a thankless task, but it will show in the finished product.
Step 6: Finishing and Painting
Once the helmet is at this stage, you can decide to add a crest. I have seen good examples that use an old brush for the crest, but I wanted a horse hair type crest. This is much easier since the horse hair simply fits into a piece of tube on the dome of the helmet.
I began with an overall coat of red oxide primer, mostly to seal everything in, but also by unifying the colour you can see the surface patina. I decided that the slight imperfections in the dome were in keeping with a Spartan helmet. I next glued the PVC pipe in place with two part epoxy glue and left it overnight to dry.
I painted all the lower surfaces matt black using a brush. I painted the area around the crest joint with bronze using a brush, this will ensure that the joint looks natural later.
Then I lightly over sprayed the dome with black allowing the red to show through.
I added a splash of colour using purple for a bit of interest on the faceplate.
Next I dry-brushed on bronze to cover the dome and bring out the ridges in the face. I then dry-brushed a little gold on the dome and silver onto the face. I continued doing this in light passes until I was satisfied with the depth of colour.
Step 7: Final Flourish
Finally I went back with the airbrush and some black to make the light areas stand out a bit and we're finished.