03-03-2003, 06:15 AM
How do you bore out the drones. I can figure out how the rest of the pipe is made but not inside the drone. Thanks
I use gun drills. These allow bores to be cut very quickly and accurately.
For the counterbores in the tops and middle joint I usually use a long boring bar which will give a perfectly straight and cylindrical result. But because it's wood, it will still move a little, so I always ream the counterbore too. (A boring bar is a tool which cuts with a single edge, is attached to the tool holder of a metal lathe, and is fed using the travel on the lathe. It is not a pub where there are no drummers.) One problem with the boring method is that the "overhang" on the bar is very long and chatter can result, where the bar vibrates and gives a very bad finish. So the right tool is critical, along with the right "feed rate", spindle speed, etc.
The tops are very time consuming to bore, as they have work at both ends, so after the main bore is done, the counterbore, or "tuning chamber" as I call it, has to be cut, and the piece also has to be cut to length so the bell and bush thread can be cut at the other end.