I got some iTunes gift cards for my birthday awhile back, finally redeemed them. Was gonna toss the cards, then realized they are a good thickness of plastic. About .030 on my cheap digital micro. Might look at your gift cards and see if you want to save it for plastic. Just an idea.

Jerry ,
I use old credit cards/gift cards at my garage all the time for dash work or interior trim work where you need to release clips behind the trim and not mar the surface. I also use them as a squeeqies for the foil tape and decals but never really though of cutting them into strips…suppose could be good shim material…