So now it my turn to school you.......Foam-board will not sand, nor can you get it smooth in any way shape or form. The laminated paper prevents this and the foam will actually dip deeper in than the outer layer of paper giving it a concave appearance. I tried for hours to get is smooth but no luck. I took thin craft foam and covered all of the exposed areas that showed all of the layers. I know you can't see it clearly, but the entire perimeter of the body of the DMR has craft foam covering it. Even the bottom of the magazine, hand guard (in and out) and the grip. Use contact cement and not hot glue. Hot glue will leave lumps in the foam. Again, exp talking.
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