Tuesday, March 21, 2006

Duct Tape

Many people know the benefit of collecting fingerprints from duct tape. By using either the sticky-side method or the Liquinox method (I prefer Liquinox) you can develop some outstanding ridge detail on the glue side of the tape. It works exceptionally well in a laboratory environment, but not so well in the real world. The biggest problem comes from trying to unravel the duct tape from whatever disformed shape it was in when you recovered it. I have tried several possible solutions to this problem including an oily substance specifically designed for this purpose (which dissolves the glue and the print). Only one method works reliably and that is... refrigeration.

I prefer to place the tape in a refrigerator for several hours before trying to unravel it. In severely sticky cases, you might have to place the tape in a freezer instead of a refrigerator. If you do not have access to a refrigerator or freezer, you can use liquid nitrogen, but it isn't very practical and it's not readily available. However, there is a portable method that can be purchased at any electronics or home-improvement store. Canned Air. If you hold the can upside down while spraying, it emits an incredibly cold mist that will freeze anything in its path. Cover the duct tape with this mist and let it sit for a few minutes - it is almost as good as placing it in a freezer. Please be extra careful if you use this method! The mist will absolutely freeze anything in its path - especially human skin! It will cause a very painful injury that takes an enormous amount of time to heal and will cause severe scarring. That having been said, it works great on duct tape.