John Tuttle recently mentioned that he sometimes used paper for bleeds.
If anyone else attempts this, they may get double-crossed. While one
player I know of used paper bleeds, it was a special, no-acid paper
which was very heavy and the hole punched very clean. I frankly don't
see how they did it.  But paper pin holes have not been successful for
very long, getting easily clogged with dust, due to the fuzz and
irregulatities which accompany all paper holes that small. I suggest
using someting more substantial, like heavier foils called shim stock,
or bleed cups already made and sold by the Player Piano Co. These cups
press fit into a 5/32" hole and will flush with a 7/32" spot-face if
you need them to.

The bleeds I wish I could find are the little "tubes" made by Amphion.
They look to be about 3/64" OD, peened and drilled on one end to the
desired bleed size.

Ampico did a lot of research on bleed sizes, and discovered that the
flow through a bleed was not only dependent on its diameter, but also
its position relative to the walls of the tube it was in. This flow
could be decreased by half simply by offsetting the little bleed hole
by just a few thousandths off center within the bleed tube!

Bleeds are tricky, and when you are striving for uniformity within a
note stack, it is not wise to believe that just because all your bleeds
are the same, that your valve response must be the same, too. Player
mechanisms are very simple mechanically, but commensurately more
sublime and difficult to troubleshoot, as well. As the performance
requirements increase, tiny, otherwise insignificant differences
between valves increase, too. That is what makes reproducers
challenging. Without question, consistent results in reproducing pianos
are the most difficult of all to achieve, and become the greatest
achievement in all "pneumatic-dom" when perfected. It was within their
venue that all the necessary precision measurements and discoveries
required were actually made.

Craig B.