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20240427.md

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 And now the inserts fit in on the template, and they're gluing now. I'm also gluing the
 BK12 and linear rail inserts for both the Y axis and Z axis, which is all the gluing I can do until
 I drill more holes.
+
+## Clockmaking
+
+I've been reading "The Modern Clock" by Ward Goodrich, original version publish 1905. I am becoming
+intrigued by the idea of trying to make an accurate pendulum clock. Goodrich suggests:
+
+ * pendulum should be suspended on a spring, not a knife-edge, string, or pivots
+ * the pendulum mount should be fixed firmly to the wall of the building
+ * the crutch pivot needs to be inline with the pendulum pivot axis so that the crutch doesn't slide up/down the pendulum
+ * you can make a temperature-compensated pendulum by making the rod out of something that doesn't expand much with
+   heat (he suggests wood!), and making the bob out of something that expands a lot (zinc), and mounting the bob
+   at the bottom of the pendulum, so that the expansion of the bob moves the centre of mass upwards by the same amount
+   that the expansion of the rod moved it downwards; why did Harrison have to overcomplicate the matter with the gridiron?
+ * the pendulum bob can be very heavy, he suggests about 15kg
+ * the adjustment nut should have graduations around the perimeter to allow moving it by an angle that would cause 1 sec/day
+   of rate change
+
+I also like Hefetrueb's clock ( https://www.youtube.com/watch?v=Q9XJ3UHtpf0 ) but I don't know if I'd want the
+grasshopper escapement. I do like the idea of reducing the number of wheels by making the escape wheel go around
+once per 4 minutes and making the dial show seconds on 1/4 of a turn. I also like the roller pinions and anti-friction
+rollers, although I would use PTFE or something instead of lignum vitae.
+
+I am not sure why Harrison used a remontoire on a weight-driven clock.
+
+I think it would be cool to make the clock run for 1 year on a winding, not sure how practical that is though. I don't
+mind dedicating the entire height of the room to it, so the weight can fall the entire height of the room. And for that
+matter you might be able to put a vertical date scale, with a pointer on the weight!