Clock escapement file.

[Joe Hillmann]

213841

Here is the file. On top are the assembly instructions. If you notice the gear only has 27 teeth instead of 30 so that means it will only do 54 ticks per minute, which is why it requires a longer pendulum. If it had 30 it would only require a 29.1 inch simple pendulum.

[Gary Hair]

Thanks Joe!

[Michael Hunter]

Thanks from me too!
I have an almost-clock, which is waiting for an escapement. Although mine needs 18 teeth, I can see how yours is supposed to work and hopefully I can base mine on it.

[Joe Hillmann]

Michael, I don't know how you figure that you need 18 teeth, but if you actually do this escapement will NOT work. Because of the geometry this escapement has to have an odd number of teeth otherwise it can not turn.

And to anyone else who trys to build this. Do NOT use any type of lubrication (any type of oil or wax will cause it to have sticky spots. Powered graphite might work but would turn the whole thing black.

[Michael Hunter]

Good point Joe!
Maybe I could use your design (with 27 teeth) and adjust the pendulum to suit - at least to start with.
I didn't have many teeth because I wanted a long pendulum, but getting one that works at all would be a bonus.
Once it goes I could try out one with a smaller (odd) number of teeth.

[Joe Hillmann]

Michael,
How long of a pendulum do you plan on using? I had designed one with 20 teeth but because I have 8 foot ceilings I gave up on it since I figured it wouldn't fit.

[Michael Hunter]

Joe
My clock is based on an epicyclic geared clock by William Strutt, designed in the early 1800s. The original design was for a small mantle clock with a very short pendulum and fast tick.
The original escapement wheel had 36 teeth, but there was no detail given about how to make the escapement itself - "every clockmaker should know how to make these" said the book!
I had changed the gearing and halved the number of teeth in order to get a pendulum length of about 4'.
The escapement seemed to work "by hand", but I never got it to run with weights and a pendulum for more than a couple of seconds. There are several possible reasons for this -
1 The wheel was not giving the pendulum enough "kick" to keep it swinging.
2 Just too much friction in the wheel/escapement/pendulum drive mechanism.
3 Far too much inertia in the whole clock mechanism. (The weight drives the hour-hand spindle in order to get a decent running time between "windings")

What you can't see from the picture, is that the clock is regulated via a small pinion running on the outside of the large ring-wheel, which turns about 10x faster than the minute hand.

I think the best for me to do is to copy your escapement as-is. If it runs at all, then I can see how fast or slow the clock goes and then adjust the gearing, pendulum length etc. to suit.