Yes, you can easily sew through PVC foamboard. The picture is of 1/8" foamboard sewn with a size 22 needle, and size 92 thread at 5 stitches per inch.
PVC foamboard is the perfect thing to use for door panels, it is very strong, it cuts and shapes easily with normal wood working tools, it's half the weight of solid PVC, and it's completely waterproof. It also cuts easily with a utility knife. If you drill holes, either use Forstner bits or spade bits, but Forstner bits are the best. Once you try it, you will never use cardboard again. It is available in a lot of thicknesses, and my supplier has 4' by 8' or 5' by 10' sheets if I need them. Look for it at a sheet plastic supply place, it'll be a lot cheaper there. If they don't understand when you ask for foamboard, it's also called expanded PVC, closed cell PVC, or foamed PVC. Brand names are CelTec, Sintra, Komatex, and Palight. I'm sure there are other brand names.
No one lives forever, the trick is creating something that will.
Last edited by DanTwoLakes; 11-10-2012 at 08:03 AM.