So here is the reference pic!
Basically, there's a few different methods for going about making something like this.
First method is using a computer program called Pepakura, which takes a 3D model and then can convert it into 2D which you can actually print out on paper. Looks something like this.
You print the 2D pieces using cardstock and glue them all together which gives you the 3D model!
Lots of people paint the cardstock with fibreglass resin to give it extra strength and then coat the outside with bondo or some type of automotive filler. They then sand away and the bondo which gives them a nice smooth, durable surface which can then be painted and sealed.
There's also approach number two.
This method uses pepakura but instead of using cardstock, the 2D images are used for patterns to trace out onto foam. EVA foam. The type you see in gyms or in little kid kindergarten classes that all fit and are all colorful and what not.
Looks something like this:
Fairly thick stuff. The one in the picture is 3/8" thick. It can be molded into different shapes with heat so it can molded to curve or wrap in whatever way you need.
I decided to go with this method. Foam is a lot more flexible then the fibre glass method and also a lot more light weight.
I'm only using pepakura for specific pieces though. Like the shoulders bells. Everything else I'm doing free hand by tracing the pattern out onto poster board then using that as the pattern for the foam.
Here's my shoulders in progress; using pepakura
All these pieces need to by glued together to make the shoulder. Doesn't really look like much now.
Why not use pepakura for the entire costume you ask?? Good question! It's because if you look at Samus, her proportions are totally warped.
Her shoulders and chest are super huge and very broad. Her head is SO tiny. Her waist is like mega thin. And her legs are scary long.
It would take a ton of tweaking to be able to get the correct proportions for everything and it's extremely time consuming. So no. No pepakura for that.
So I started off with the easy part - which I think is the arm cannon.
I took poster board and wrapped it around my arm to give me an idea of the correct length and width I wanted the cannon to be. I then took that pattern and transferred it onto some foam.
I don't have pictures because I decided to document my progress after I made that part but all it really is, is a square piece of foam which I rolled up to make a tube. I used the heat gun to heat up the foam so it kind of rolled up by itself then connected it with hot glue. Voilà! A tube! This is the base of your gun!
That's what it looks like glued together. To get the curvature part at the end I used pepakura to help me get the right shape. Then connected it all with hot glue. I made two circle things on the side of it and will add more detailing with craft foam because it's not as thick as EVA foam.
...and here it is detailed and ready to be painted! Just waiting on some stuff I ordered from Amazon so I can start painting it...