Ten years ago there was a construction article authored by John Wilding published in the English Horological Journal on building a six minute weight driven pendulum operated egg timer. Knowing that I liked such things fellow hobby machinist, Pete Larsen shared the article with me, however it just sat dormant until a couple weeks ago. It was a fairly simple project and a pleasure to build. It is equipped with an unusual MacDowell single pin escapement that is interesting to watch. It is self starting and with pendulum bobs both above and below the pivot it acts somewhat like a balance wheel. It is easy running and requires only small weights, but they fall fast. About 40 inches in six minutes. A suitable bell could not be readily located So one was spun out of 1/16" sheet brass. That turned out to be a day long project in its self.
Timing eggs or not, it is interesting to watch. Take a look.