Saturday, February 25, 2006


After spending about 18 of the last 22 hours working on design finalization and template layout, the templates are finally in the hands of the Kinko's in Fairbanks. We'll be able to pick them up on Monday. The reason it took so long was that I had to do some significant last minute design changes. One of the main purposes of the plywood escapement was to experimentally determine the amount of time the escape wheel has to turn from one tooth to the next. I had estimated half a second, but it turned out to be about a third of a second. This small difference caused the anticipated required sled weight to increase from 103 pounds to 220 pounds!

Fortunately, I was able to drastically reduce the weight to 83 pounds by scaling down the escapement and the last couple gears in the gear train. Unfortunately, it was the kind of change that affected many other things. Quite a few parts had to be re-drawn, some extra parts for the gear tooth cutter had to be worked out, and I had to start over my template layouts from scratch.

Meanwhile, Lars has finished his home-made lathe and is proceeding with his bandsaw for slab cutting. We had been counting on being able to rent a 48" bar chainsaw in case the bandsaw doesn't work, but that plan has fallen through. Now all our eggs are in one basket, and our second best option is a smaller bar chainsaw that would be rather suboptimal. Go, Lars!

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