So I have been scouring the internet to find a way to make the breastplate for a femtrooper and kept running into the same problem, everything is designed for women with a normal sized bust. Which left us bustier girls out of luck. then I stumbled upon a gent that was making mass effect armour for his wife by screwing 2 round things to a board and stretching eva foam over it. (here is his blog Evil FX / BioWeapons.com | Custom Costume Builds ) but the same problem came up, where am i going to find something that is big enough and round? Well, I was making dinner one day and pulled my dollar store strainer out of the dish washer... and, well colour me pink it sure did fix mighty nice!
So I went to the dollar store and got 2 and removed the handles and hot glued them to a dollar store cutting board.
I used one of those cheep wal-mat puzzle mat and a heat gun to mold it over the base I made. then just cut it out and heated the sides and bent them in place so it curved around my chest.