So, I stumbled upon something called “pepakura” while browsing the net. Seeing as it was pretty much described as “easy process, awesome results”, I decided to give it a try. I am, after all, an avid maker of things.
A brief browsing through The RPF showed me that the hip thing that the kids these days are building is an Iron Man helmet. Why not? I downloaded the pepakura viewer program and the Sharkmark VI Iron Man helmet PDO-files, and had a look at the files.
The tester helmet has around 250 tabs to glue, while the actual helmet has around 1100. Making the tester seemed to make sense, so I got to work.
Seven hours of cutting, folding and gluing got me something resembling the picture on the proverbial package.
I had already learned a couple of things:
1: 160 gram paper isn’t quite thick enough. The resulting build will be floppy. I ended up adding additional support structures inside the helmet to try and make it stay in shape.
2: There’s a _lot_ of fiddly small cutting and gluing involved! Some of the folds are so ridiculously small that they are impossible to do even on 160 gram paper. I have no idea how that’s meant to work with thicker material. I ended up using extra pieces of paper to extend the small flaps so that there would be enough surface area for the glue.
Well, so far so good, kind of. I also decided to go through the whole process of making the helmet with the tester as a practice run. I’m already glad I did.
Next up: Fiberglassing the inside. I read somewhere that it’s a good idea to apply one layer of resin only first, so that the weight of the glass mat doesn’t bend the helmet out of shape. Makes sense. I applied a liberal amount of resin on the inside of the helmet, using a paint brush. Working around the extra supports inside the helmet was a bit of a pain, but I managed. I hung the helmet upside down to cure.
The next day I came back to the workshop. The resin had cured nicely. But… It would have been a better idea to leave the helmet so that the extra resin could run out of the helmet. Now I had a nice big chunk of cured resin at the top of the helmet. Well, nothing that a bit of relentless Dremeling couldn’t fix.
While working the extra resin out, I managed to Dremel my way through the top of the helmet in a couple of places. Oops. I also tore the helmet in a couple of places with the Dremel’s cord. Oops. No biggie, those were easy enough to patch with a piece of aluminum tape, and the first layer of fiberglass should do the rest.
A bigger problem was that the helmet was bent out of shape. And asymmetrically, as well. My paper support weren’t doing as good a job as I hoped they would. So, I added some wooden supports this time, hoping that the first layer of fiberglass would set the helmet in a shape that would be at least symmetrical if not completely correct.
I applied the fiberglass to the back of the helmet, and left it to cure.
That seemed to work quite well. There were still some distortions in the general shape of the front of the helmet, so I added another set of supports before fiberglassing the front. I attached the helmet to a wooden frame to keep it in the right position while I worked on it.
I then added a layer of fiberglass to the front of the helmet.
I came back to the workshop to find a nicely cured fiberglass shell of a helmet. The shape was nowhere near perfect, due to the floppy paper original. But, at least with a solid fibreglass piece, I could now get to work on fixing the shape.
A only had time for a bit of sanding and adding a set of fiberglass filler (the blue-green stuff). The final shape of the helmet will be made with regular auto-body filler, but in places where I wasn’t convinced the fiberglass was going to end up being thick enough, I decided to use the fiberglass filler to reinforce those places.
Continued in the next post.