Hey there! I sometimes see questions on reddit when fellow 405thers post, and there's always the inevitable "how the heck can I do that?!" and here's my TL;DR version of armor building for the Pepakura method.
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Pepakura is the way I did my first suit.
Go here and find the model you want(there's tons more models, but this is a great start. If you want more models, search the 405th, or google in general and you'll find what you're looking for!), and get
Pepakura Designer.
Scale your piece to your size.
Once you've done that, you'll need to get 110 lb cardstock paper. Print it out, cut it out,
score each fold and glue the tabs together. (hot glue, elmer's glue and/or super glue are some common methods!)
Once you've got your
paper model ready, make sure it has supports, then you can fiberglass it. Fiberglass the first layer, but do a very light layer so your paper doesn't warp. Once you got an initial layer then you can really lay it on, and get a bunch of layers on it. You can use Fiberglass cloth on the inside for added strength.
Then.. get ready for the fun part!
SANDING (no, im kidding, I very much dislike this part!) Lots and lots of sanding. You might want to even do a bondo layer.
Once you've got the sanding done, then you can
paint!
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I highly suggest going through
this thread Find the suits you really like, and see if that person has a build thread. Then go through their entire build thread. See how they did different parts.
Longshot-X,
DavidDuffy,
Halex,
Spitfire22V and
Carpathia's --These were just a few of the many amazing build threads I went through for guidance and assistance in building my first suit. Go through their threads, find others you like and go through theirs. Bookmark and save pages that you'll know you'll need; its a pain when you saw a really good tip, but its buried in 12 pages of replies when you just want to see how they did their strapping on their chest!
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This is just how I learned, and its probably not the best way, but it worked for me (and I'm still learning new things every day, I love it!). This forum has a WEALTH of information and it just takes a bit of research to find what you're looking for. Folks here are incredibly generous, helpful and are willing to assist in any way they can. This is seriously my favorite community and I feel so lucky to be a part of it!
If you have any questions, feel free to message me and I'll try my best to answer and help out.
Welcome to the community and I look forward to seeing your build thread!
hence the name (starting off with some homework) Ill make sure to research all current and past builds so I can get a good idea for the creators and others in the 405th. 
