njs ... what rappel device did they recommend for the 7 mm cord? Can you give us a brand name, or better still a link on the Web?

Otherwise, I tend to be in agreement with an opinion expressed above that you are taking a serious risk by trying to rap using paracord. The chances of getting into a free-fall accident are high. Not to mention the nasty burns you would get on your hands. People who do fast rappels either use special rappel devices (e.g. caving gear), or fat ropes (military).

other Pete