Hi All, It was very interesting to me to read all of the opinions
and comments regarding the issue of pouches and sealants. The age
old question, "To seal or not to seal," doesn't really seem to have
The truth is, it's an extremely important question, and understanding
when, where, and why a pouch should or should not be sealed, and
which of the numerous sealants is best suited for a particular task
in a player or reproducing piano is one that every rebuilder (novice
or professional) should consider carefully before making a decision.
To that end, and in an effort to expand the knowledge base with
regards to pouches and sealants, Craig Brougher has written another
detailed article called "Pouching Valves". Some of the topics he
covers in the article include the fundamentals of valve operation,
when is it necessary to seal a pouch, leather selection, sealants,
and the effects that various sealants have on both the leather and
the internal parts of the player mechanism.
For the time being, this article is available in the PDF format.
Ultimately, it will be available as a web page, complete with an
embedded video of the test jig that Craig built to show why making
the right choices is so important. That video is currently at YouTube,
but it doesn't have much relevance without the information in the
article. The article is located at
(Looks the best at 130% magnification.)
The video is located at:
Also included within the text of the article are over a dozen pictures
which help bring depth and clarity to the information. And, at one
point, Craig shows that he still has a sense of humor even in the midst
of a serious topic.
As a final comment, I want to note that during the testing that Craig
did, he made an unexpected discovery which I believe all technicians
will, as he did, find surprising. One other thing that I already knew
about Craig, which you can't help discovering for yourself after you
read this article, is that he doesn't rely solely on experience when
it comes to making decisions. He designs and fabricates tools to test
out his theories, with the goal of finding out the real truth.
John A Tuttle
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