/cgl/ - Cosplay & EGL

Working with Eva foam for the first time. Working on leg armor. I have a leg dummy that I wrapped saran wrap and clear tape around. I drew the armor pattern on it, cut it out, and laid it on my foam. When I cut it out and pieced it together, it was too small by a pretty decent amount. Laying the pattern on the inside of leg piece shows just how much bigger the pattern is than the armor. Is it something to do with how I'm laying the patterns for a curved leg piece flat and then cutting and bending the foam? Am I laying the pattern on the wrong side before cutting? (I'm laying it on the smooth side then cutting and forming, with the patterned side on the inside)