Having spent some time on the Devon Sea Clock the following notes might help anyone trying to work on the grasshopper escapement.
What struck me as a potential issue was the lack of repeatability of the curly whirly leaf springs used to activate the grasshopper pallets. As the clock arrived with me, these two springs were far from identical in their shape. This worried me but I stuck with them initially.
After spending many hours I finally got the clock running but the springs still did not feel like they were a good solution.
I stripped down the centre bosses and began to consider the idea of replacing the spring with simple compression springs. Fusion 360 was calling.
I created an infill plastic boss to sit between the two brass plates of the centre boss. The two bosses are identical. The insert sat over the internal spacer pillars the central post. I then put two M3 holes through the boss to allow an adjuster screw and a small compression spring to fit in each and act against the pallet ends.
Difficult to explain so here are some pictures.
So far it seems to work and I am slowly bringing it on time with the Microset Timer.
Update – Clock now running pretty much to time and is keeping to a few seconds per day. Really pleased with the outcome. Microset is a wonderful piece of kit that lets you see all that is going on with a movement.