FEATURED WEB SITE: COIN SHRINKING
The E-Sylum (5/30/2010)
This week's Featured Web Site is suggested by Kavan Ratnatunga, who came across it while searching for other things. David Fanning introduced the topic to us in 2006, and Coin World had articles on it as early as 2002. It's a neat little scientific demonstration - check out some of the videos on the site.
NOTE! The information on this site is for educational purposes only. It is not to be construed as advice on how to build or use similar equipment. Electromagnetic Forming is an extremely dangerous high-energy process that can maim or kill a casual HV experimenter!
The Quarter Shrinker utilizes a technology called high velocity electromagnetic forming, or "Magneforming". To shrink coins, I charge up a large high voltage capacitor bank consisting of a number of large "energy discharge" capacitors. Applying a 6,300 joule pulse results in a quarter whose final diameter is about 0.1" SMALLER than a dime! The largest coin I've shrunk was a Silver Eagle, a silver coin that starts out being about 1.6" in diameter, and ends up 1.3" in diameter afterward. At 6,300 joules, a Morgan silver dollar is reduced from about 1.5" to 1.25" in diameter, and a clad Kennedy half dollar is reduced to a diameter smaller than a US Quarter.