1. Blocked Tracker Bar: frequent occurrence.
Clear the tracker bar with the suction bellows or trackerbar pump, aided if
necessary with a strip of wire; but in every case see that
the accumulated paper fibre is cleared out.
2. Blocked Tracker Tube: frequent occurrence.
Slip off the tube from the nipple and blow the dust FROM
the tracker bar: If the tube is of metal, unscrew the tube
rail and do likewise.
3. Leaking Primary Pouch: rare occurrence.
Place a tuning wedge, or a flat strip of wood, over the
bleed hole, and covering the tracker duct blow to the
tracker bur: Seccotine (fish glue) is reliable for gluing down a lifted
pouch.
4. Clinging Primary Pouch: rare occurrence.
This is caused by the pouch clinging to the glue, or size,
with which the pouch chamber is lined. Blow French
chalk beneath the pouch.
5. Stiffened Primary Pouch: frequent.
Caused by damp. Rub the pouch well with French chalk,
or better still replace with a new and supple pouch.
6. Slack Primary Pouch: frequent.
A slack pouch fails to lift its valve. See that a cardboard
disc is glued, BY ITS CENTRE ONLY, to take up the
slackness, and that the valve button is just clear of the
disc.
7. Enlarged Bleed Hole: frequent.
Glue a piece of stiff paper over the old bleed hole, and
, pierce a smaller bleed.
8. Sticking Primary Valve Cap: very rare.
Sift French chalk beneath the valve cap by a thin knife
blade or similar tool.
9. Tight Primary Valve Stem: very rare.
Reduce the stem by scraping with a knife. To strip a primary
valve, scrape off the glue on the primary cap and
punch out the stem. The stem is only secured by the touch
of glue on the cap.
10. Insufficient Primary Valve Movement: Frequent.
Slip chalk beneath the primary valve and twist the valve
to each face until sufficient movement is obtained; or; in
cases of excessive damp, release and reglue the stem.
11. Loosened Primary Valve Stem: very rare.
Clean and reglue the stem, observing the correct movement,
- approximately one-thirty-second of an inch.
12. Blocked Secondary Air Channel: rare.
Clear dust by means of a piece of tubing or wire.
13. Leaking Secondary Pouch: rare.
Glue down, or fix new pouch.
14. Clinging Secondary Pouch: rare.
Blow in French chalk, as in No. 4.
15. Stiffened Secondary Pouch: rare.
Proceed as mentioned in No. 5.
16. Slack Secondary Pouch: frequent.
If the disc is all right, turn back the valve to just clear
when pouch is deflated.
17. Sticking Secondary Valve: frequent.
Sift French chalk beneath the valve discs and their seats.
18. Stripped Secondary Valve Stem: frequent.
Thread a new leather disc on the stern, or replace the disc
itself:
19. Insufficient Secondary Valve Movement: frequent.
Adjust the movement of the valve by twisting the discs (if
threaded), or reducing the washers in other cases.
20. Leaking Pneumatic: rare.
Slip a knife beneath the pneumatic; force it off; re-cover;
and glue it down carefully when completed.
21. Broken or Displaced Pilot: rare.
Send a pattern to the suppliers.
There are really only two considerations covering these
defects, and they may be summed up in the one word, - valves,
the horizontal and the vertical. When dealing with the former,
one cannot mistake the pouch board with its thirty or forty
screws that being removed exposes all the secondary valves.
The vertical valves are usually in two or three tiers, and the
action in these cases has to be withdrawn and unscrewed at the
bass and treble ends by sections to gain access to the pouches.
There is no real difficulty in dismantling a player; but great
care is necessary in re-assembling, and every attention must be
given to the tightness of channel boards, tubes, and air trunks.
THE CYPHERING NOTE
In all probability, the next most familiar trouble to the dumb
note with which the tuner has to deal is the cyphering note.
This is readily identified when the tracker bar is covered and
pedalling causes a hammer, or hammers, to rise to the strings.
The double valve player produces, approximately, eight
causes for this complaint; but our old enemy the damp is
responsible for the majority of these, as indeed it is in a high
percentage of player defects generally. Proceeding from the
tracker bar, cyphering is almost certain to be caused by:
1. Leakage, or Disconnected Tracker Tube.
This condition is frequently met with. If the tube is of
rubber; in the course of time it cracks at the point where it
covers the nipple, or short metal tube, in the pouch or
channel board. The remedy is obvious. Renew the tube;
and for this purpose the tuner should carry a few feet of
different sized tubing with him. However; should the tubing
be of metal, the trouble is probably caused, not by a
puncture, but by the tube springing from the nipple at the
tracker bar.
When the tube is located, by unscrewing the spool box
panels, a touch of Seccotine (fish glue) round the nipple will overcome
the difficultly. But care must be exercised that no
film covers the mouth of the rube, or a dumb note will
result.
Should the leakage be where the tube enters the pouch
board, draw out the end carefully from the socket and
apply just sufficient Seccotine (fish glue) to produce a slight bead or
collar on replacing the tube.
2. Tight Primary Pouch.
This again is of frequent occurrence and is invariably
caused by damp. After removing the primary pouch
board, see that the valve is nor resting on the pouch.
When at rest, there should be a slight space between
pouch and valve. This space varies in different makes;
but observe the adjustment of neighbouring satisfactory
pouches. The tight pouch is holding the primary valve
from its seat, and air is in consequence passing to the secondary
pouch. The correct method is to dismantle the
valve action and remove the primary set, so as to expose
the pouches. Should these be old and stiff; it is better to
renew the lot; but if comparatively new, sprinkle French
chalk over the pouches and rub them down with the
thumb. This stretches the pouch leather and permits the
valve to seat. Test each pouch before re-assembling, in
order to see that the rubbing down operation has caused
no fracture in the pouches.
3. Defective Valve Cap.
This is rare. Occasionally foreign substances - a splinter
of wood, a chip of glue, and so on - may lodge beneath the
valve cap and hold it from its seat; and in rarer cases still,
the years have hardened the leather face of the cap to the
leaking point. Obstructions beneath the cap can be
removed with a piece of piano wire; but if the leather is
indeed too had to be airtight, chip the glue from the valve
cap, punch out the stem, and re-cover the cap with a disc
of sheepskin, observing when you replace the stem that the
valve has the correct movement, as indicated by its neighhours,
and remembering not to glue the stem, hut only to
apply a touch where the stem emerges from the cap.
4. Obstructed Bleed Hole.
This is a rare occurrence, and is attributable to the dead
air beneath the pouch failing to exhaust through a completely
closed bleed; the pouch inflating, cyphering follows.
Clear the bleed with a piece of fine wire.
5. Leaking Secondary Air Channel, or Tube.
A frequent source of annoyance. Should the screws holding
the channel boards to the air chest have stripped and
fail to hold, air is liable to pass into the channels, the secondary
pouches being thereby inflated: or if a screwdriver
too wide has been used carelessly, the screwhead sinks
into the channels, with the same result. The screwholes in
such cases should be plugged, and fresh holes bored
adjacent, but of course between the channels. If tubes are
employed, proceed as in the case of No. 1 defect.
6. Tight Secondary Pouch.
To make good this frequent defect, remove the pouch
board - or, in the case of vertical valves, dismantle action
- and proceed as in No. 2.
7. Defective Valve.
Foreign substances will be found frequently to have
lodged between the inner valve disc and its seat, causing
the striking pneumatic to collapse. If this is so, clean
with wire; but should the valve be stripped, one must
unscrew and lift off the valve seat, threading on a new
disc, or discs, in place of the old. In the course of time,
these discs are liable to set tight on the stem: and, if they
are not exactly at right angles to the stem, they are liable
to cypher In that event, work them slightly, until quite
flexible, so that the main exhaust may draw them tightly
to their seats.
8. Leaking Pouch Board.
Proceed as in No. 5.
THE NON-REPEATING NOTE
It is a question whether my next section should not have
headed the list of pneumatic player worries, for it frequently
occurs in the dry, as well as in the damp-affected instrument.
However, it shall be our next consideration. The non-repeating
note is common in all players that do not receive the regular
attention of the tuner or player expert. The trouble is frequent,
and is usually the result of
1. Obstructed Bleed Hole.
Should the suction bellows fail to clear the bleed, it is
necessary to unscrew the primary valve board, or slip,
and clear the bleed with fine wire. It i.r then advisable to
clear the lot at the same time.
2. Loose Tubes.
This trouble is rare. When a tube is leaking, yet not sufficient
to produce cyphering, the rapid deflation of the
pouch is greatly affected, and in consequence the repetition
also. Make sure that the tubes are perfectly airtiqht,
as in dealing with a cyphering note.
3. Stiff Pouches.
Again rare. Damp-stiffened pouches affect adversely the
repetition. Proceed as in No. 2 for a cyphering note.
4. Insufficient Valve Movement.
This is frequent, and is caused usually by damp swelling
the leather valve faces. If a primary, rub down with
French chalk (see instructions for a dumb note in preceding
section) and increase the movement of the valve. If in
the secondary, and the discs are threaded on the stem,
turn up the disc until the valve has sufficient play; or; if
the discs are adjusted to the stem by washers, reduce their
number to obtain the same result.
5. Too-great Valve Movement.
A trouble frequent enough. I f the valve is not stripped,
turn back the disc to the desired movement. In the secondary
valve, this should be approximately one-sixteenth
of an inch. If dealing with a primary, see that the stem is
not loose and that its movement is a little less than one
thirty-second of an inch.
6. Stiff Pneumatics.
The only, though expensive, remedy for this somewhat
rare trouble is to cover the whole set. In unshipping
pneumatics, if the moveable leaf is cut off, a hot iron will
speedily loosen the glued base.
7. Broken Pneumatic Spring.
Rare. Some player pneumatics are provided with a light
spring at the hinge of each. In the uncommon event of
these springs breaking, the rapidity of the pneumatic's
movement is considerably reduced. Lift out the ends of
the old spring with a knife and fix a new one of the same
sized wire.
8, Lost Pneumatic Motion.
Set up the metal capstans to the action butts. In the case
of an old instrument, re-clothe the butts and regulate all
capstans to the touch.
In dealing generally with player troubles, a great deal must
be left to the discretion of the tuner or mechanic. For instance.
the question of valve regulation can only be answered by considering
the size of the pneumatic to be exhausted. Some of the
large pneumatics of twelve and more years ago require a valve
motion of about one-eighth of an inch to ensure rapidity of
action; but with the greatly reduced size of the power pneumatic,
the modern valve itself has lost considerable bulk, and in
consequence is satisfactory with half its former movement.
LOSS OF POWER.
The loss of power in the pneumatic player is generally the
result of a leakage in the main bellows, in the valve chest, or in
the large tubes connecting one with the other; though occasionally
the valves themselves are faulty, and only experience will
enable us to locate rapidly the trouble. It is well to bear in mind
that vast importance of obtaining as air-tight a condition of the
whole player as is humanly possible; for, it we regard the valve
chest as a box from which we have greatly reduced the air pressure
by pedalling, it would need only a few punctures such as a
bradawl would produce to considerably reduce the vacuum, or
power. And if only half-a-dozen valves, which are each about
the size of a shilling, fail to seat perfectly. then six shillings'
worth of power is immediately lost.
Naturally, when I speak of "vacuum," my readers realize
that I use the word in a figurative sense only. A perfect vacuum
would burst in every pouch and pneumatic with which we have
to deal. What occurs when we operate the pedals is that we
considerably reduce the atmospheric pressure in the valve chest,
and the admittance of normal air produces sufficient work to
operate the action of the piano on its way to restore the balance
again.
Let us proceed, then, from the source of power - the main
bellows - and endeavour to locate a weakness, or lack of
response, dealing with the defect when found. In the first place,
push the playing lever to re-roll, which cuts off all power from
the valves, and, gripping the motor, pedal vigorously. If the
bellows are sound, the pedals will quickly "pull up," and the
reservoir (or equaliser) expand very slowly. Should the reservoir
open rapidly, the trouble is in the bellows set, and we must
now disconnect the wires that pass into the control boxes (do
not disturb the inside buttons, as these will give the correct
adjustment when replacing); unscrew the bellows from any
backstays or the floor of the piano; slip off all exhaust tubes,
and lift out the bellows set bodily. When on the bench, we can
glue small patches of leather over the trunk holes, and operating
the pedals - or pumpers, if the pedals are detached - get at every
part of the bellows and test thoroughly.
A leakage usually develops at the corners and angles of
reservoirs and pumpers; and, if too far gone for patching, cut
paper patterns of the correct size and re-cover with the rubbered
cloth obtainable from the supply houses.
The modem reservoir is supplied with a trap which, when
unscrewed, exposes the springs and interior screws holding the
reservoir to the bellows chest. In some models there are exterior
screws through two or more blocks. When the reservoir is
detached, it is easily recovered. The pumpers have generally to
be cut away from the chest before it is feasible to re-cover
them. Before replacing, see that the flap valves are perfectly
soft and pliable. If time has hardened them, remove and
replace, as it is most essential that these valves, especially those
between pumpers and reservoir, are quite air-tight. If they are
not too ancient, they can be greatly softened by rolling between
the palms of the hands, and stretched to a condition that will
give satisfactory results for some years. Observe if the governor
bellows are quite sound before replacing the bellows set.
Let us assume that the bellows are now as tight as can be
desired; and that, having replaced them and connected them up,
we are still dissatisfied with the result. In that case, we shall
have to carry our investigations to the upper regions, - that is.
the wind chest. If we find that the valves have sufficient movement
to exhaust their pneumatics rapidly, it will be necessary to
dismantle and unscrew one of the central valve seats. The edge
may be corroded with a sort of verdigris where the seat meets
the leather disc; if that is so, unscrew the seats, and either rub
them down on a perfectly flat sheet of fine glasspaper, or provide
a new set.
Perhaps the valve discs are too tight on their stems, and fail
therefore to come back snugly to their seats, or they may be cut
or worn at the surface. New valves are the remedy in this case;
or, if the surfaces are good, gently work the discs until they are
flexible. Remember that only a very few leaking valves are sufficient
to reduce the power to a wretched state of inefficiency.
Glance at the pouches, and see that they are not damp-stiffened.
If they are, rub them pliable with French chalk. Finally,
examine the pneumatics and see that they have not developed
small but terribly effective holes at their comers and angles. It
is not advisable to patch these small and sensitive pneumatics,
for, no matter how carefully the work may be done, they are
liable to be considerably stiffened by this process, and are in
such cases extremely unsatisfactory. Unship the lot and recover
with rubbered cloth prepared for the purpose, taking
every care that your strips of cloth are wide enough to permit
the pneumatic to open as fully as it did originally, or you will
let yourself in for a peck of trouble.
After these operations, I venture to think that the response
of the player will fully justify the labour and patience expended
on it, and that it will in every way come up to expectations.
And now let us turn our attention to the motor. The usual
complaints are a jerky motion, too great a speed under heavy
pedalling, and too slow a movement when speed is indicated.
The jerkiness is as a rule attributable to one or more of the following
defects.
1. Tight, or Unburnished Slides.
Unscrew the guides and blacklead and highly polish the
motor face and slide faces; and, should the guides press
on the slides in the slightest degree, glasspaper the former
until the slides are perfectly free.
2: Leaking Slides.
I If the slides are worn, or grooved, place a sheet of fine
glasspaper on a perfectly flat surface and rub down the
slides until they are quite airtight.
3. Badly Regulated Slides.
When the motor pneumatics are collapsed, and again
when they are FULLY extended, the lower edge of their
slides should be JUST UNCOVERING the bottom ports.
Regulate the buttons to obtain this result.
4. Tight Shaft and Connections.
The shaft should he almost loose in its bearings, and the
slide and pitman connections the same. If tight, ease
bearings with a rat-tail file. Never oil, as this swells the
cloth bushing.
5. Tight Collars.
These are sometimes adjusted too close against the brackets.
Allow about one eighth of an inch lateral movement
of the shaft.
6. Leaking Pneumatics.
Carefully patch with thinnest of leather; if the powers are
not sufficiently worn to need re-covering.
7. Stiff Pneumatics.
In rare cases the pneumatics have "set, " and stiffened,
especially at extremes of extension and contraction. By
disconnecting the pitmans and pressing the pneumatics
lightly, afterwards pulling them out to their fullest extent,
they are greatly eased and are more pliable.
8. Tight Spindle Brake.
The brakes are usually adjustable, and it is only necessary
to turn hack, very slightly, the roundhead screw
attaching the brake spring to its block.
9. Loose Spindle Brake.
Should the brake be too feeble, the roll winds loosely on
the take-up spool, and at the end of a long roll a had jerking
often results. Tighten the brake spring.
10. Tight or Loose Chair.
An "idler wheel" as a rule takes up the slack of a chain:
but in the fixed type of idler if the chain is too tight, it
pulls up the motor; and if too loose the chain may jump off
the sprocket wheel. Adjust by releasing the locking screw
on the fixed idler spindle, ease, or take up slack.
11. Tight Metal Gearing.
A touch of oil is necessary where metal passes through
metal bearings, as, if the bearings are too dry, they are
liable to tighten on a long roll.
12. Too Powerful Spindle Spring.
The spiral spring in the left hand spindle is occasionally
too strong, and at the end of a long roll assists to pull up
the motor. Take out the spring from its socket and cut off
a couple of coils.
13. Weak Governor Spring.
This is also the cause of a motor failing to register the
correct tempo. Vigorous pedalling in such n case tends to
cut off too much power, even to the point of jerkiness.
Strengthen the governor spring by adjusting the locking
pin, if dealing with a spiral; or if with the V type, open
out the spring an inch or two. If ,on the other hand, the
speed is too rapid and the motor "races" on heavy pedalling,
it is necessary to weaken slightly the governor
spring, remembering always the standard speed of seven
feet a minute with the tempo indicator at 70.
In conclusion, I should say that I have, of course, only
touched upon the fringe of troubles to which such a complicated
piece of mechanism as the pneumatic player is prone. An
ocean of minor defects still lies before the virgin keel of the
beginner: but in those seas Experience only can be the navigator
to bring the tuner safely to port.
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