William, darn it, I thought you were buying me one for my birthday!
I would be very interested to see how it turns out. I have spent some time on designing a jacot drum for my Wolf Jahn 6mm but decided against making one as I am just so used to polishing pivots by hand in a block of lignum vitae with the arbor held in a pin vice. I would have killed for one at the start, it took me a while to learn how to file a badly worn pivot straight and then to get a satisfactory polished finish with the pivot file/burnisher. If I was as rich as William I would have just gone out and bought myself a machine or the proper lathe attachments . As I go through repairing clocks I see some awful work that has been done to them previously, I think this could be on the rise again as people just cant afford the proper tools for the job and there isnt enough decent training opportunities in this country any longer to make sure work is done properly. Its ok reading books to get a general idea but having someone tell you how to do it or where you are going wrong is priceless.
Seeing the prices pivoting attachments make on e-bay these days is a good indicator of where to start, along with the jacot drum, the most useful items that almost always seem to be missing from a used watchmakers lathe.