Hooray for Geometry!

Last Saturday we did a training session for the youth group going on the Mexico mission trip. Since we had a bunch of youth graduate last year, the group is smaller than it's been for a while, so we're allowing 8th graders to go on the trip, too. We've got a bigger group going to Mexico than last year, but overall younger and less experienced. As always, should be fun but interesting. And tiring for me, both physically and mentally. It's only a 6 day trip, 2 of those days traveling, and we build the house in 3 1/2. It's a lot simpler than houses here: slab foundation, roll roofing, no electrical, plumbing, wall sheathing, insulation or drywall. But it's all by hand, including mixing the concrete. One of the most tiring parts for me is that I'm with people all the time -- tough for an introvert.

This week I've been working on the electrical and siding. The electrical is pretty simple, though 3-way switches are a bit tricky, and a 3-way switch with 2 lights between and the fewest wires is like spaghetti. I can't imagine what 3 lights would be like (which would be required for the lights in the lofts...) Fortunately there's an easier way to do it, by wiring it as you would for a single light between two 3-way switches, and then connecting the lights together with a normal 2-wire cable. It 'wastes' a wire, but it's a whole lot easier to do and be confident of no mistakes.

The other challenge this week was putting siding on the west wall. I finished up the east wall with its gable end, and moved to the east wall when I had a full day of good weather. The west wall has a gable above (5:12 pitch roof), a gable below (5:12 on one side, 3:12 or so on the other) and a round window. I was trying to figure out how to mark the curve on each board to match the window. I could measure the distance of the top and bottom from the other end of the board, but how to mark the curve? I knew I could cut a big piece of cardboard the radius of the window and use that, but I didn't have any big pieces of cardboard I could cut up. So I remembered something from geometry class lo those many (many) years ago. Given two points on a circle and the radius, you can find the center of the circle. From there, it's easy to draw an arc along part of the circle as needed: