In yesterday's Digest Leonardo Perretti gave us a nice explanation
about using a cone to produce nice fittings for organ pipes.

In "Orgelbouwkunde", the major Dutch handbook on the building of
church-organs, the use of a "cone-shape incandescent" tool is
explained as follows:

   The holes in the upper board are burned in with a red hot
   cone-shaped tool, thus causing a bowl in which the foot of
   the pipe fits.

   This burning gives a slightly carbonated surface, which
   protects the metal of the pipe from the effects of the acids
   in the oak wood.

Another effect of this carbonating: the mouth of a metal pipe is
rounded in the same way as the hole is burned in, and the carbon is
also a sealant against leakage.

Mechanical organs do not often use metal pipes: they get out of tune
more easy, they are more difficult to produce, and so on.

And, of course, it's easier to mount a wooden pipe on a wooden
pipe-stock.

Jan Kijlstra