I have recreated my Mass Effect 2 N7 armor based on the 2012 version I created (R.I.P.).
I'm still using Styrene for the torso section of the armor, but this time with a 6mm craft foam backing to help make it much more flexible and lighter (instead of multiple layers of styrene). I re-used parts from my old armor to speed things up a bit.
For the arms I am using two different sets of craft foam "Foamies" in black. 3mm sheets and 6mm sheets. Each sheet was about $1.49 at Joanne's.
For rounded off edges on the foam I used a Dremel with that weird "cone" bit at highest speed to grind the edges a bit.
I also used a heatgun to lightly brush the foam (while already in shape) to change the texture of the surface, it became smoother, much more sandable (320 grit paper) and took to paint much better.
If you have any questions about any part I made, how I made it, feel free to ask. I enjoy helping people as much as I can with costumes.
The "Self Pat on the Back since I managed to get it done at the Con Again" Award.