Hi all. Well I am in need of some advice here. I have an English
George Rogers player with Otto Higel action.
I am having trouble maintaining good suction without hard fast pumping.
There are two combined pneumatic stacks/valve chests. The upper tier
operates the even numbered notes, the lower tier operates the odd
notes.
The pneumatics are OK. There are no leaks around them. The inside
valves are fairly straightforward - double on thin threaded metal
stems. The upper valve facing is leather on an slightly wobbly
aluminium? serrated disk. It seats to an aluminium? cover plate
shaped like a bell. The plate is held in place by inverted Y-shaped
fibre guides. The lower valve facing is leather on a hemispherical
wooden button. It seats to a metal grommet shellacked in to the valve
chest.
The wooden button is _screwed_ on the to stem so as to achieve
rigidity, air-tightness, and proper vertical alignment. The metal disk
and wooden button are tight together on the stem separated only by a
very thin leather washer. Thus the valve travel is fixed according to
the thickness of this assembly. Adjustment to valve travel (due to
slight differences in the position of the lower seat) are by paper
bell-shaped shims beneath the cover plate.
The whole upper action is a very efficient-looking outfit, and as the
natural position of the valves when at rest is vertical, gravity should
assist good lower valve seating.
I have done the following:
1. Rebushed the Y shaped fibre guides. Many were missing/moth-eaten.
2. Releathered the upper valve disk with good quality pink calfskin.
(Maybe it is pigskin). It is smooth suede on the glued side and shiny
on the facing side. I do not detect any hissing from these facings
during playing.
3. Releathered the lower valve button with very thin pouch leather --
smooth Zephyr Skin.
The original leather was slightly thicker with a suede (but not shiny)
finish. I changed this for two reasons - Firstly I understood that
Zephyr Skin was simply the best, and secondly I considered it important
to maintain the overall valve travel. Putting thicker leather on would
have meant new shims (and PPCo do not stock this type). I have not
opened up the pouch chest as it all seems good. I have therefore not
repouched, or reshellacked the grommets. All of the gaskets look fine
and the screws are all tight. I do not think that there is leakage
around the edge.
The results of all this are:
All notes play on a test roll. Repetition is good. I do not detect
any indication of the pouches holding up the valves. I have
specifically checked for this by _very_ gently blowing down each tube,
whilst holding down the valve stem, and I can just detect initial
movement of the pouch before it makes contact with the stem. No notes
play when they should not.
Despite all this I can hear movement of air in the valve chest when
pumping. Oddly enough it is _seems_ more apparent in the tenor and
treble areas but this could be my hearing. There are two suction
inlets to the chest, one at each end. If I pump really hard the action
does seem to tighten up and I think that the movement of air reduces.
Questions:
Are my lower valve facings really leaking? Have I used the wrong
leather? If so what should I use on this type? Shiny face or suede
face? I have been very careful when gluing, and the wooden button faces
were super smooth before I applied the new leather.
Am I missing something? Can I apply any other test to pin down the
problem?
Thank you for reading this far! I look forward to hearing from anyone
with experience of this type of deck.
Roger Waring
roger.waring@dial.pipex.com
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