This note was sent to me by Craig Brougher.
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From: firstname.lastname@example.org (Craig Brougher)
To: email@example.com, firstname.lastname@example.org>
Date: Fri, 17 Jul 1998 07:33:44 -0500
Subject: Auto-typist pumps
Hi fellows, Just saw your suggestion about Auto-typist rotary pumps.
I've used them and love them, but they will not work at all for player
pianos, the way their valves are configured! Better warn your readers
that those flap valves MUST be changed first.
Each of the flap feeders have to have a minimum of four times more
square area of holes under them than the square area of the supply
hole, which as you say, must be bored out. I recommend Changing out
all the old flaps for new ones too, because the old ones won't seal
over the larger holes.
If I recall, I tried a "Baldwin pumper" Style of flap using a round
aluminum plate and coil spring, and four large holes in a circle
because of the area available, but I think that about anything would
work as long as it doesn't weaken the bellows too much.
The further the flap has to move, the noisier, by many times, the pump
[ Thanks, Craig and Philip. Nothing can beat the advice from one
[ who has 'been there and done that' a few dozen times! -- Robbie