Without a doubt, one player piano valve that has impressed me is the
Simplex. These little valves work very well with a range of travel
of 0.028-inch to 0.032-inch and are airtight.

I have enclosed some photos of the construction showing the layer of
pneumatic cloth under the leather. The pneumatic cloth is on the valve
between the leather and the wood part of the valve. It is slightly
smaller in diameter. The hole in the middle helps center the two.

The glue is placed on the wooden part of the valve and then the pneumatic
cloth, followed by the leather. This method has the leather only glued
on the edges of the wooden valve allowing the vacuum to pull down on the
leather making an airtight seal. The pneumatic cloth is not glued to the
leather. A very clever method of making an airtight valve.

I use a Mayhew punch set to make the valve facings. These punches punch
both holes at the same time. The little clamp to hold the valves for
glueing is a machinist stop clamp for a vise that is very handy for
holding small parts also. And of course hot hide glue -- always!

Don Teach
Shreveport, Louisiana

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