For a long time I've been curious to jump into the world of costume building, and this Christmas break it made the perfect project. I dived head first into the fun and quirky world of Pepakura.

Pepakura is a program that takes 3D models and unfolds them into a series of 2D pieces that can be printed out and assembled. I am new to the hobby, but I've noticed major issues with a lot of the tutorials currently available; they lack information on the finishing process. Browsing through Google and costume forums a lot of people have taken great care to cut, fold, and glue beautiful paper models, but when it comes to painting and detailing the end product, the project goes awry.

My experience is in that finishing process. The main focus of this tutorial will address the painting and detailing stages of a build, taking you from paper to Iron Man (but actually War Machine), hopefully giving you some tips and insight along the way.

Pepakura, from my limited experience, is relatively straight forward but time consuming. Many communities exist on the internet that have posted models and files and many of the major movie and video game icons already exist. This makes the hobby accessible for people like me who want to jump in and try it out without the need to first create a model of my costume on the computer. Take advantage of these communities, they are a resource with experienced users who are willing to help.

DISCLAIMER: This project uses harmful chemicals and tools that must be handled properly. If you are unsure how to use a tool or chemical consult the user-manual or contact the manufacturer. The internet is also a great resource. Make sure to work in well ventilated spaces and take breaks when/if you get annoyed. The work can be tedious, but it is important to keep focused and take your time. One silly mistake or botched fold can mean headaches down the road. Be smart about it. I am not responsible for any injury or damage caused by this project or tutorial. Work at your own risk.

With that said, let's jump into what you need to get started.

Step 1: Materials & Tools

The materials for this project are widely available and easy to use. Please keep in mind however that some of the materials are toxic. Work with care and make sure to read the instructions.

Items in italic with an * are optional but recommended.

Initial Model:
Cover Stock/Card Stock/110lb Paper
X-Acto Blade/Cutting Blade
Hot Glue & Gun
Computer and Printer

Strengthening:
Resin
Disposable brushes (4+)
Fiberglass
Rubber Gloves
Respirator
Mixing Cup (top of Resin container works well)
Spoons/Mixing stick (mixing)

Finishing and Detailing:
Bondo
Sand Paper (150 grit)
Sanding Block
X-Acto Blade
Mixing Cup/Paper Plate
Spatula/Flat Object (used to apply and spread Bondo)
Plastic Spoon/Mixing Stick (mixing)
Nail File (Emory board, can be cut to get those hard to reach places)
Safety Glasses
Bastard File*
Dremel w/ Sanding bits*
Orbital Sander*

Painting:
Automotive Primer
Colors of Choice
Gloss Clear
Wet/Dry Sand Paper (400 grit+)
Dish Soap
Tack Rag
Painter's Blue Tape
X-Acto Blade
Respirator

Lighting:
Refer to my other tutorial here. Shameless plug ;).

Step 2: Pepakura to Assembly

The best of part of this project is browsing through the hundreds of available models online and choosing which one you want to make. The most established models are those for Halo, but Iron Man, Star Wars, Tron, and many more exist. I suggest thoroughly searching the web for what costume is right for you. I've included links on my link page to some of the more popular websites and genres. Have fun!

Once you have chosen what costume you want to build you will need to download Pepakura, found here, and make adjustments to the layout of the unfolds and the scaling or sizing of the piece. For information on using Pep look here, it includes information on rotating pieces and moving them around. The wiki for Pepakura is loaded with information, and looking around before your build can only help. I have tried to distill much of the information here, but my goal is to add new information about a build and not to summarize. As a result I may link you to other articles along the way.

Each model will have a different scaling, so make sure to do some background research before printing it out. If you cannot find information about scaling do a test with a bicep piece. The helmets are often the most complicated part of a build and not something you want to cross your fingers for. *I didn't heed my own advice and my helmet is too small* Generally if you can get a bicep piece to fit correctly you have an idea of how to size the helmet.

I found these video tutorials by Youtuber Abrant3 helpful. He explained the scaling very well for his Halo costume model. Even though this is an Iron Man tutorial, and Abrant3 did Halo, he discussed a lot of the techniques for this build clearly. I recommend browsing through his stuff.

After scaling is complete, and you've laid out your pieces to be printed, double check that you are printing to the correct size paper. Some of the models have been unfolded for A4 as opposed to the American standard, Letter paper.

Print out your model on the 110lb paper and prepare for several hours of cutting. I enlisted a friend here, which made the process go much faster.

My helmet had 13 pages of densely packed pieces to cut out. If you aren't phenomenal at using an X-Acto blade, expect to be. I recommend practicing first on scrap paper to get a feel for how hard you have to push down and how the blade handles in the thicker paper. I tried to cut all of my pieces in one pass, which saved time, but also meant that one slip could be extremely detrimental. However, if you slip on a tab piece, which is primarily what you will be cutting out, it does not particularly effect you. The shape of the tabs, with the small ones being the exception, does not generally matter.

Take your time and take breaks. The cutting does not need to be stressful. Find a rhythm and cut away.

Once you have everything cut out, the project becomes an interesting combination of a jigsaw puzzle and origami. Before folding the tabs I found it easiest to score along the lines and then make the appropriate fold. I scored the paper by gently running the blade over the lines. This does take some practice. I recommend cutting a scrap piece to get a feel for the right pressure.

There are two different kinds of folds that are indicated by a --- (dash-dash) or -.-. (dash-dot). The dash-dash is a mountain fold and the dash-dot is a valley fold. These names should make sense with the kind of fold. On a mountain fold, the line becomes the ridge, with the paper on either side folded down. Likewise, in a valley fold, the line becomes the bottom of a trough. Refer to the pictures below for what these folds look like.

To attach all of the pieces I used hot glue. It solidifies quickly, is cheap and easy to work with, and is strong. I used small amounts on the tabs, occasionally burning my fingers tips, and was able to quickly put the helmet together. If you misplace a piece you can also gently pull them apart, remelt the glue, and reposition. This comes in handy.

When gluing, do your best to make sure the numbers are adjacent to each other and touching. This is your best indicator that everything is fitting together correctly. Once you have assembled to your piece, it is time to strengthen it.

Step 3: Resin & Fiberglass: Strengthening

My Iron Man helmet has several pieces that are meant to be separate, but for the purpose of the resin and fiberglass I attached all of the pieces with paperclips and binder clips. This was to insure that everything fit together correctly. I was concerned that if I did each piece independently there was no way to guarantee the pieces would match up. In the below photo you can see the inside of the helmet and the clips.

After I had everything connected and held together I took a lot of time to make sure the helmet was the shape I wanted. I checked for symmetry and made adjustments where possible. It is critical that you take the time to make sure you have the right shape before adding the resin to the outside of the piece. Once you add the resin the shape will be fixed.

You are going to add resin to the outside, without fiberglass, to solidify your shape. The piece is still somewhat flexible even with the resin, but it can support itself. The resin allows you to cut away and trim any support pieces prior to adding the fiberglass.

*When working with resin keep in mind that it is toxic. Take the appropriate safety steps, such as wearing gloves and working in a well ventilated space.*

The resin is easy to work with but you have to work fast. Have a plan before you mix your resin on how you want to apply it. At this stage you are simply going to brush resin on the outside of your model. Follow the mixing directions for the resin, and be consistent on how you mix your batches. I used small amounts at a time because of the short window you have to work with it. I chose areas of my mask to paint and got to work.

Be aware that if you pile up too much resin in one area it will drip. Try to evenly spread it around your work area. My particular resin took two hours to cure, but I only had a 10 minute window to work with it. I followed this schedule fairly religiously for applying my coats. Each area only needs to be hit once because you are not trying to make the helmet indestructible at this point, that comes later.

Be absolutely certain that every bit of paper gets coated. I wasn't careful enough and missed some of the paper near the neck region. This causes issues later when applying the Bondo and paint.

Once the entire model has had resin applied to it and has cured, remove the support structures. On my model this meant trimming the neck area and some of the internal pieces. Trimming the helmet will facilitate applying the fiberglass.

*Fiberglass can be nasty. If you handle it with bare hands or it gets on exposed skin it can be painful and dangerous. Wear a mask, eye protection, gloves, and long sleeves at this stage. Keep in mind that you are working with fine glass.*

When you purchase fiberglass it comes in large sheets. These sheets need to be trimmed into strips for you to apply to the inside of the helmet. I used larger wider strips on the top (3” wide x 6” long) and sides of the helmet and smaller and thinner ones (1.5” wide x 3” long) for the detailed areas such as the chin and face mask. You will have to adjust for what works best for you, but make sure the fiberglass is in the cracks and crevices as best as possible. Be generous with the resin at this stage, making sure to saturate the strips. The fiberglass is messy and will stick to anything and everything. Although it looked funky, I wore trash bags on my arms. It made it less messy and easier to clean up when I stuck my hands inside the helmet.

We will be able to go in and trim the inside a little after we have applied the fiberglass, but try to make sure there are no pieces poking out all over the place. I used woven fiberglass fabric, but others have used normal fiberglass sheets without problems. Both should be available at your local hardware store.

I placed my fiberglass strips in the helmet and then dabbed them with resin to position them. This method worked well for, but experiment to find what works best for you. Others glue the fiberglass in place first with a dab of hot glue, but it was easier and faster for me to do it the way described above.

Make sure to fiberglass the entire inside of the helmet. You do not need to overlap or double up on fiberglass, but you can. Once you are finished with the fiberglass it is time for the Bondo stage!

Step 4: Bondo

From the beginning of this project the Pepakura model has simply been a foundation, with the idea that any imperfections and the final shape and design would be fixed by Bondo. It isn't a cure all, but Bondo can do some amazing things.

*Once again, you are working with a toxic material. Work in a well ventilated space. Keep in mind that Bondo, when sanded, creates a very fine dust that will coat everything.*

I mixed large batches of Bondo at a time and had a game plan in mind before applying it to the mask. This made my use more efficient, particularly because of the short window you have to work with the body filler. Even though you will be sanding the Bondo, if you don't try to maintain the basic shape of the helmet and various areas while applying it, it can become tricky. Refer to the pictures below for images of my Bondo before and after sanding. Notice that the grooves and details are still outlined.

For the larger areas I highly recommend an orbital sander. Although a bit fancy for a DIY budget, it will save you. You can use sand paper, but an electric sander will be worlds faster. I also recommend a Dremel. With the various tips and attachments detailing the helmet becomes much easier. A Dremel is a great investment that is incredibly useful for many projects. Food for thought.

When I did my first pass with Bondo I wasn't trying to be perfect. I was only trying to build up my layer of filler. If you look at the pictures below you will see that even on the sanded areas there are still imperfections. The idea is to get the entire thing more or less covered before going back and really perfecting everything. With that said, I did sand between each application of Bondo. This let me check what areas needed to be built up more, etc. Take your time and don't get discouraged. This process can be time consuming, but it is what will make or break your project. It is your last opportunity before you paint and finish the project to correct detailing issues.

Once you have built up the filler it is time to work on the detailing. Again, I was concerned about the symmetry of the helmet. With a lot of projects online the most noticeable mistake is unsymmetrical sides and rough finishes. Make sure to look at your piece from different angles and sand down and correct the shape.

For the rough sanding I used 150 grit sand paper. The use of a sanding block made it easier to sand down the curves, and the orbital sander was a life saver. Be aware of how quickly a Dremel and orbital sander will remove material. These devices work much faster than you sanding, and as a result it is easier to momentarily loose focus and cut too deep into the Bondo. I punched through the actual shell of my helmet several times. These gashes weren't serious and were easily fixed, but they took time to correct. The buzz term situational awareness applies. Do it.

Besides the Dremel, which is great for the small fine detail sanding, a nail file also works really well. This will come in handy for sharp edges and curves. You can also cut the nail files into thinner strips to get to those hard to reach areas.

If you decide to use a sanding block, keep in mind that you can easily make one. This may be helpful for the smaller flat areas of the face. Any piece of wood with sand paper wrapped around it works.

If you have gloves left over from the previous stages of the build you can also smear bondo into cracks with your finger. This is sometimes easier than using a spatula. You can also use cardstock or thick paper, folded up several times, to apply Bondo into small areas.

Once you have the Bondo finished, hit it with some higher grit paper to make sure it is smooth. Run your fingers along the helmet to feel for bumps and rough spots. Some of these areas may become more pronounced once we start to paint it, and we will have an opportunity to come back and touch them up. Make sure you are satisfied with the Bondo, because it is time to paint.

Step 5: Paint

Painting is a tricky ordeal that requires patience and attention to detail. With a controlled environment, delicate handling, and the right techniques, your helmet will come out shiny and professional. Don't get discouraged in this stage. If you mess up the paint you can always sand it down and restart. I will go through the process below and discuss what works best for me, but feel free to change it where you feel comfortable. Fingers crossed that all goes well.

The first step in this process is selecting the proper paints to use. These can be found at any hardware store. Companies like RUST-OLUEM and Krylon are reputable and are carried by most stores. Once you've decided on the colors you want to use you will also need automotive primer and high gloss clear. The primer usually comes in a light or dark gray. If you are using darker colors, like I did, choose the darker gray. This isn't critical to the success of the painting stage, but it makes things a little easier. If only one primer is available do not worry.

I would recommend setting up a basic spray booth. This will help protect your piece from dust while protecting the surrounding environment from over-spray. I tilted a cardboard box on one side and taped the flaps open.

The process for painting is as follows:
Ghost/guide coat (very light and speckled coat)
1-2 light full coats

A ghost coat is a very very light coat that looks speckled. You are not going for full coverage, it just sets the stage for the rest of the coats. Allow this coat to dry for 15-30 minutes and then wipe your helmet with a tack rag. This will remove any loose paint and impurities. Now apply a full coat. You want to keep your coats light and allow adequate drying time. Avoid too much build up and pay attention for drips. Make smooth, even strokes with your hand to keep every pass consistent. Begin spraying to the side and off of the piece, then drag your hand over the helmet. This protects you from splatter when you first spray the paint. For the primer, 2 full coats is adequate. After you finish a coat wipe the helmet with a tack rag. Once you have finished with your primer, and you have even, consistent, coverage, lightly wet sand the piece. Wet sanding is simple, but you must be careful not to remove too much of the paint. Using a very fine grit paper, 400 and above, run the piece under warm water and apply dish soap. Begin to lightly sand. This will remove and burs and help get the surface smooth. Thoroughly rinse the helmet to remove any soap and let he helmet dry completely.

Rub the helmet down with a tack cloth and choose your faceplate color. This color will be applied directly to the helmet without any areas masked off. Try to keep the paint limited to the faceplate region. Follow the process outlined above, and coat the helmet until you are satisfied with the color. If the paint is rough, you can wet sand it, but make an even pass with the color afterward. For this stage, never end with sanding, always end with spraying a coat of paint. Let the paint dry completely. Unfortunately, once you begin to apply color, particularly with silver and brighter paint, the imperfections will begin to become more visible. You can either sand the paint down and fill in the imperfections, or do as I did, and write this off as battle damage … right?

With the faceplate painted we need to protect it from the main body color. For this use painters blue tape. The tape is easy to use, but must be applied only after the paint is completely dried. I applied my tape too soon and peeled off paint when removing the tape. Make sure when applying it that it is sealed to the helmet. Run your fingers along it to push out air bubbles and use an X-Acto blade to trim away excess. Be careful not to cut too deep when doing this, it is easy to damage the paint underneath. Take your time to make sure no areas of the faceplate are exposed. When applying the tape use the largest pieces possible. This will help when it comes time to remove it.

Follow the same process for painting the faceplate when spraying the main body of the helmet.

Once you are satisfied with the color of the body and have given it ample dry time, carefully remove the masking tape. When removing the tape pull it away from the painted area. This will help to ensure crisp lines between the two regions.

I was unhappy with my helmet because it lacked detail. I decided to highlight some of the curves and edges by lightly brushing silver onto them. It isn't obvious that silver was added, but the edges stand out more and the monotony of the black is broken up a bit. In order to do this take a paper towel, lightly spray your color on it, and gently brush it along an area that you want to highlight. This takes a little practice but can really improve the overall look of the helmet. Careful not to overdue it though. It is easy to get carried away with it.

I mentioned earlier that when I removed my masking tape I also peeled up some of the paint. There are several options to fix this. You can either gently sand down the area, mask if off, and paint it again, or you can apply paint to the area with a Q-tip. This won't look as smooth, but if the area is small it isn't noticeable. Because I was starting to get tired of this project and really wanted to finish it up I chose the Q-tip method...

Wipe the entire surface with a tack rag and apply a ghost coat of clear. With clear coat, the more coats you are willing put on the better. I generally make these coats heavy, walking a fine line between nice paint and drips. Wet sanding is generally done at this stage, but it is easy to sand through the clear coat and affect the color underneath. Be careful if you do this.

Once the clear has cured for a day or two you can also wax it. I used turtle-wax to bring out the extra gloss I wanted from my helmet. Polishing compound can also be used, but be careful as you are removing material and can go through the clear coat.

Step 6: Detailing

The last step before you have a finalized piece is adding the extra details. This includes the LEDs for the eyes and extra pieces here and there. As I'm sure someone will point out, my helmet is not a true Iron Man or War Machine helmet. It is based on War Machine, but I took some artistic liberty with it. After all the work I had put into it I decided I wanted to make it mine.

I chose to add some mesh to the front and ignore some of the details of the War Machine model. The mesh also allowed me to hide some of the rougher areas of the helmet. I first cut paper to get the right shape and to test the fit. I then traced the shape onto the mesh and glued it in place.

I did the same to seal the bottom of my helmet since it was intended to be a show piece. I cut the bottom out of black foam board and built a small stand out of the same material.

The LEDs are not difficult to do yourself. I realize that some of you may have never done anything with electronics before, but now is the time. I wrote a tutorial 5 years ago on wiring and working with LEDs. Check it out here. Hopefully it is insightful and you know everything you need to in order to make some LED circuits for the eyes. If this is unclear and there is a demand, I will add a detailed description of doing the eyes. As of now I haven't done them but I will in the next week or two.

Step 7: Conclusion

This project was a great intro to the world of Pepakura and was a lot of fun to do. I like Pepakura not only as a costume making technique, but also a prototyping one. With that said, I don't know that I would jump into Pepakura again for a project that requires a lot of detail, mainly because with Bondo I couldn't do everything I had set out to. I was unable to remove all of the imperfections and get all of my edges. For $50 I am really happy with the outcome, but I still think it could be better. I spent about a week, a straight week, on this project. I got a lot out of that time investment, but I got bored and tired of the tedious and menial task of sanding Bondo. At the end of the day, Pepakura is better suited for a project with edges, not something like Iron Man who has few definitive corners. This is a great technique, but it is reserved for Master Chief and other characters.

If I went back to this again I would have chosen clay, rather than Bondo, and tried my luck at mold making. I think I will do clay in the near future because of the level of detail that is achievable. Who knows, perhaps I can do a tutorial on that too.

Overall this is a great inexpensive project that will teach you a lot. From working with fiberglass to painting, it has some great techniques that are applicable to a plethora of projects.

This turned out to be a long tutorial and I'm sure I wasn't able to cover everything. If you have questions, concerns, etc, post them below. I'll be lurking around to help others out. Thank you for your time, patience, and attention. Good luck with your build. If you found my tutorial helpful please help me out by voting this tutorial up for the laser cutter contest up above.

Happy building,
O'Malley