I posted this on your other thread..
I use polyester resin without the wax in it.... If it has the wax you will have to sand it everytime you glass something else... Without the wax you don't have to sand between glassing..
I use the chopped mat.. And remember this one rule... If you don't want a line to show when your done glassing,, Don't cut it with a scissor,, Tear it, That way when your done glassing everything will look better... I hate it when I see guy's glassing things in a car and you can see the lines on EVERYTHING they glassed in.. It might be covered with Interior.. But I know it's there..Do it right, Or don't do it at all..Good luck.