Mark,

I stay away from staples for the same reason that you do. Instead, I choose to use regular old clear cellophane scotch tape - about a 1-half inch piece works great. I use 3 pieces per flip (one piece on each open end - see scan).

I have over 2700 chips in cardboard flips secured with this method and have never had a problem. Looks great too as it is hardly even noticeable.

If I want to get the chip out, I simply stick a pocket knife blade in the slit and cut the tape (on one of the openings only) - the chip will slide out easily. It is equally easy to slide the chip back in and re-seal in the same flip with another piece of tape. If I open the same chip about 5-6 times or so, it is not difficult to peal off the outer layers of tape (or simply replace the flip with a new one).

Hope this helps...Jim