Pepakura is a program that prints 3D models onto paper in 2D. This is one of the most popular methods of making "Halo" armor. You fold and glue the pieces together, and then use a fiberglass or other kind of resin to make the model rigid, then you can do the detail work, make it look nice, and make a silicon mold from there to make your final piece.
This is still a work in progress but I figured I could write down the steps I'm taking along the way.
I found a pepakura file for the Green Ranger Helmet on Rangerprops.com and figured it would be a good way to see if I liked the pepakura process. It was my first time doing it, and it wasn't nearly as hard as I thought it would be to figure out. It was printed on thick cardstock paper and cut out with an exacto knife. I managed to get all the pieces cut and glued together in a day. A long day, but a day. As you can see, it is a tad too small height wise, so it will be extended after it is coated in resin.
Here are the pictures after the first two coats of fiberglass resin. It is pretty straight forward. Follow the mixing instructions on the back of the fiberglass can, it helps to have dixie cups or disposable measuring/mixing cups. I applied the resin with a small strip of cardboard because I didn't want to mess up my brushes.
Apply it in sections. Front, back, left, right. You can probably do two sections at once if you mix a full ounce of resin. Wait a few hours between coats.
After several more coats of fiberglass resin(yes, I got kind of sloppy towards the end, and theres a chunk of a washcloth stuck to it that I will now have to sand off), I decided it was rigid enough to cut. I tied a string around it to create a guideline and cut the halves apart with a dremmel. I will put spacers in once I determine exactly how much height I need, and then I will lay the fiberglass and the matting down on the inside, and fill the space on the outside. Once it is extended I'll sand everything, put on more resin, and repeat until I have a workable surface. After that I will use auto body filler and Aves Fixit Sculpt to do the detail work. Anyway, here are the new pictures.
I used cardboard strips duct taped to the outside of the helmet to space the halves about an inch apart all around. I ended up having six strips total for support but the photos show the first four. After that, I fiberglased the inside over the gap as well as over the visor hole. I will do the entire inside for support as well as to give it some thickness to work with. I will be sanding and resining the outside until I have the basic shape down and then I will start doing the filling and detail work.
I sanded the exterior of the helmet and applied a decent coating of spot putty over the entire surface. It took about three days to fully dry. I then hand sanded with 60 grit sandpaper to knock the bulk of it off. It left me with a good idea of what needs to be fixed and filled. I also did a bit of slush casting on the inside with the fiberglass resin to thicken up the top, I'm going to be doing a lot of work up there.
I put a few coats of automotive primer on the helmet that way I could see it all in one uniform color. It was hard to determine what needed to be done with the color of the paper, the resin, and the bondo all mixing together with each other. As you can see, the left lower half needs to be thickened up a bit, as well as the upper right. In between all the repeated fillings and sandings I will begin cleaning up around the mouth and visor, and eventually move on to the detail work.
In between all the repeated fillings and sandings I will begin cleaning up around the mouth and visor, and eventually move on to the detail work.
This is going to be a long project, especially once I get to the details, but I think the finished product will be pretty cool.