Your advice was great! You understood exactly what I was asking. I repaired
the soft pedal valve and made a clamp out of spring steel and used large
leather nuts to hold it and they worked fine.
I have been through the pedal regulator, crescendo valves, pump, and pedal
valves. They all look like new and work good. The piano is now tubed like
it should be and is operating great. The sub intensity is very soft and the
crash passages will blow the window out. The pump is capable of over 100" as
measured pumping by hand.
What puzzled you is now put right. The music roll brake is now tubed to the
little nipple on the back of the control valve block. Someone had tied this
off with a knot and run a tube from the music roll brake to the pedal
regulator just to get a stronger music roll brake. Probably didn't like the
large rolls to tighten during play.
NOW my only remaining problem is that the pump pressure when the tracker bar
is covered and music not playing (like at the beginning or end of the roll)
the pump pressure is only 15" and pedal pressure is 13". When the pump
pressure goes up during playing the pedal regulator works great and keeps the
pedal pressure below 17.
Question: What controls this (idle) pump pressure? How do I bring it up to
between 17 and 20"? I know if it were in that region I could then set the
pedal regulator to between 15 and 17. I haven't found that information in any
books I have on hand. I know its been on the MMD but since I didn't have an
Ampico B I didn't pay that much attention to it.
Everything is working but the rewind pneumatic and the soft pedal are a
little sluggish due to low suction.
Thanks again for taking time to answer my questions the way you did. I'm
fascinated with this pneumatic system and its simplicity of operation. I
used to work on pneumatic controls aboard ships and wish them man that
engineered the Ampico B would have built that equipment.