The use of Lignum Vitae as a bushing material for clock pivots goes back quite a few years. In fact, John Harrison, the inventor of the Grasshopper Escapement (also the brass/steel grid iron pendulum - a temperature compensating pendulum rod, and rumored to be the inventor of the ball bearing) - used Lignum Vitae bushings in his Brocklesby Park Tower Clock (then a clock over a stable) with Brass Pivots. (From "The Illustrated Longitude" by Dava Sobel and William Andrewes)
The Brocklesby Park Clock is still operating (with some maintenance) - almost 300 years later - in the near vicinity of the sea (lots of humidity, salt, cold/hot weather, etc.). Quite an accomplishment.
So - it sounds like good advice to experiment with this.
I don't have any lignum vitae - but I do have Ipe', that I am experimenting with making clock pivot bushings.
Process:
I first cut the .5" bushings from the face of an Ipe' board using my Veritas "Snugplug" tapered cutters.
Then I drill a .5" hole about .375-.5 deep, in an oak dowel mounted in the 3-jaw chuck of my metal lathe. Next I drill a 0.25" hole the whole way through the oak plug - for an ejection rod to enter.
I insert the tapered bushing in the oak dowel- and center drill, then drill an undersized hole for the clock pivot.
The final hole is reamed out slightly oversized (about .002" I think). This seems to make a nice pivot for my initial trials.
To remove I have an ejection rod that I insert into the outboard side of the headstock - and pop the ipe bushing plug out of the oak dowel.
(If you have a better idea - or questions - please post)
