Tom Smithwick has put together some resources for making Duronze Ferrules.
Text Description of Duronze Ferrules
Spreadsheet for Making Duronze Ferrules
From Tom: This was put together about 15 years ago. Bill Harms and Jim Maurer came to my shop, and watched me make some ferrules and wax eloquent about the process while I was about it. Bill kept copious notes on the process I followed and wrote the text describing it, plus a zinger or two in my direction, of course. Jim paid attention to the dimensions, and how I derived them and came up with the excel program that makes that part a lot easier. I have sent this material to a number of people over the years. I hope it fits in with the effort you guys are making now, which will be appreciated by many.
The write up was done by Bill Harms on Tom’s process. It includes a list of tools and a very concise set of directions on how to make the ferrules. The Spreadsheet is an interactive one where you enter the size of the ferrule you want, and the dimensions display on the graphic of the cutaway ferrule. This spreadsheet only works on Excel. For those not using Excel, the Zip file contains screenshots of each size ferrule with the appropriate dimension on the graphic.
Drawings:
