Originally Posted by
laurafet
All kinds of patterns available. I have found the best thing for the bottom inset is corrugated plastic. It is the type of stuff that real estate signs are made from, or garage sale signs- looks like cardboard only white plastic coated. You can get it in the hardware section of Wal Mart in a blank sheet for a few dollars. It is large enough for 2 bottoms depending on the size of your bag.
This is what I use also. I went to my local sign shop and and bought an armload of scraps for $10. I cut them with an old rotary cutter.