PianoDisc LPS User manual

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PianoDisc
LPS
Installation Manual for the
PianoDisc Low Profile System
Version 2.4
Sept. 2018
PianoDisc
4111 North Freeway Blvd.
Sacramento, a. 95834
www.pianodisc.com
[phone] Fax [phone]

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TABLE OF ONTENTS
Table of Contents……………………………………………………………………………………………Page 2
Introductory……………………………………………………………………………………………………..Page 3
Step 1 Disassemble the Piano……………………..…………………………………………….…..Page 4
Step 2 Remove the Keybed……..…………………………….……………………………………….Page 9
Step 3 – Measure the back key spacing for key solenoids…………………………….Page 13
Step 4 – Take keyframe measurements………………………………………………………….Page 18
Step 5 – Create back rail bead on keyframe in necessary……………………………..Page 20
Step 6 – Cut the keyframe………………………………………………………………………………Page 21
Step 7 – Mark the location of the solenoid rail slot……………………………………...Page 24
Step 8 – Prepare to cut the solenoid slot……………………………………………………….Page 28
Step 9 – Cut the solenoid slot…………………………………………………………………………Page 29
Step 10 – Reinforce the keybed………………………………………………………………………Page 32
Step 11 – Assemble tray, solenoid rails and guide solenoids ………………………..Page 32
Step 12 –Locating and installing service tool inserts…………..…………………………Page 36
Step 13– Cut legs to fit solenoid slot……………………………………………………………….Page 37
Step 14 – Installing the trap work……………………………………………………………………Page 38
Step 15 – Adjust key solenoid plungers……………………………………………………………Page 57
Step 16 – Installing key solenoids…………………………………………………………………….Page 58
Step 17 – Plug in driver boards……………………………………………………………………… Page 61
Step 18 – Setup for burn in………………………………………………………………………………Page 63
Step 19 – Burn in the unit………………………………….……………………………….……………Page 64
Step 20 – Install driver boards into the tray assembly.…..………………………………Page 64
Step 21 – Drill hole thru belly rail for wires…………………………………………………….Page 65
Step 22 – Mount CPU……………………………………………………………………………………….Page 65
Step 23 – Mount the power supply…………………………………………………………………Page 66
Step 24 – Mount power strip………………..………………………………………………………….Page 67
Step 25 – Install keybed to piano…………………………………………………………………… Page 68
Step 26 – Regulate action……………………………………..………………………………………….Page 68
Step 28 – Set up communication with the PD system……………………………………..Page 69
Step 29 – Adjust pedal solenoid……………………………………………………………………… Page 70
Step 30 – Final check list……………….…………………………………………………………………..Page 70
Step 31 – Ground strap installation…………………………………………………………………..Page 71
Appendix A – Keybed removal………………………………………………………………………… Page 72
Addendum 1 – Steinway Sostenuto…………………………………………………………………..Page 73
Addendum 2 – Keyframe modifications/shift lever……………………………………………Page 75
Addendum 3 – Sostenuto Jig………………..……………………………………………………………Page 76
LP Service Tools.………………………………………………………………………………………………..Page 77
PianoDisc Parts ID.…………………………………………………………………………………………….Page 80

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Low Profile PianoDisc Installation Manual
This installation manual will guide you through the process of fitting a PianoDisc reproducing piano
system to virtually any grand piano. Along with the knowledge and experience gained from a
PianoDisc Installation Seminar, this guide should be an invaluable resource.
Information contained in this manual is considered confidential by PianoDisc, and is for the sole use of
PianoDisc ertified Technicians. It may not be reproduced, distributed or quoted in whole or in part
without the express written permission of PianoDisc.
The installation instructions in this guide pertain only to the PianoDisc Low Profile Reproducing System.
PianoDisc Reproducing Systems may ONLY be installed by technicians certified by PianoDisc as
qualified to perform such installations. If you have come into possession of this manual and / or a
Retrofit Kit and you are not a PianoDisc ertified Technician, DO NOT ATTEMPT TO PERFORM THIS
INSTALLATION.
Installations not performed by a certified PianoDisc technician WILL NOT meet the requirements for
warranty protection from PianoDisc and likely such an installation would also void the piano
manufacturer’s warranty. Installation mistakes may cause violations of F regulations that could
result in an enforcement action by the F .
Technicians may be certified by attending a PianoDisc Installation Seminar. Another option for the
technician is by attending an onsite training evaluation and certification class conducted by a PianoDisc
Factory Installation Technician duly authorized to certify technicians.
A candidate for PianoDisc certification should be a Registered Piano Technician (RPT) and thus certified
by the Piano Technicians Guild (PTG). A candidate who does not qualify under this rule will be
evaluated on an individual basis with emphasis on total experience as a piano technician and possible
previous experience in retrofitting pianos with other player piano mechanisms.
In the interest of continuous improvement, we encourage piano technicians to comment on this
installation manual by writing to:
Piano Disc
4111 North Freeway Boulevard
Sacramento, A 95834
You may also fax your comments to PianoDisc at this number. [phone].
Technical support for PianoDisc ertified Technicians is available Monday through Friday, 8AM to Noon
and 1PM to 5PM Pacific Time at [phone].

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1. Disassemble the piano
NOTE: Text in BLUE refers to keybeds that are removed from the piano.
A. Inspect the piano
•While the mover is still present, inspect the piano thoroughly pointing out any damage and the
information should be documented on inspection form with the mover’s signature.
NOTE: Once you sign off on the mover’s paper work you assume any damage found on piano if not
reported.
•It is also important record the damage on an inspection sheet and pictures if possible.
B. Remove the music desk, fallboard and keyslip from the piano.
•The music desk is easy to remove as it will typically just slide or lift out of the piano. It is a good
idea to carefully place all case parts so they will not be damaged while the piano is being worked
on.
•Some keyslips are held down by a wedge between the keyslip and the keyblocks. To remove this
type of keyslip, remove the screws holding the keyblocks down against the keybed. Often there is
a folding wing nut on the bottom of the keybed making this type of keyblock quite easy to remove.
If the fallboard is not mounted on the keyblock remove the keyblocks from the piano and then
remove the keyslip.
Illustration 1 – Keyslip & screw
•Another type of keyslip is designed with a slot in the back side of the keyslip that slides friction
tight over a hidden screw in the end of the keyblock. On this style the keyslip will slide up and off
the screw head in the end of the keyblocks. (See Ill. 1)

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•Some fallboards are attached to the cheek blocks at each end of the keyboard. On this style the
screws holding the cheek blocks must first be removed. Typically the screw is found directly
underneath on the keybed. After the fasteners are removed, the fallboard and keyblocks are
removed as a unit. Be careful as the keyblocks often come off the fallboard easily when the piano
no longer prevents them from doing so.
C. Mark the location of the keyframe on the keybed.
•Make sure that during removal of the fallboard and keyblocks, the keyframe has not moved. If
there is any doubt, put the keyblocks back into place and use the keyframe guides in the keyblock
to position the action correctly. Gently remove the keyblocks being careful to not move the
action. Draw a line around the keyframe on the keybed. This will help you place the keyframe
correctly later in the process.
Illustration 2 - Marking front of keyframe
•Make side to side marks on the front rail to aid in positioning the keyframe later in the process.
Get a piece of wood (anything will do) 1 (25mm) to 2 (50mm) inches square with a square end.
(See Ill. 2) Mark 3 positioning lines between the front rail and the keybed equally spaced across
the keyframe. Place the piece of wood against both the front rail and the keybed. Without
moving the block of wood, use a pencil to mark a line on both the front rail and the keybed. These
positioning lines will ensure that you will be able to place the action side to side later in the
process.

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Illustration 3 - Marking side of keyframe
•Make front to back marks between the end of the keyframe and the keybed. These marks will
help you position the keyframe accurately front to back later in the process. Remove the
keyblocks without moving the keyframe. Using the same process as on the front rail, place the
block of wood against both the keybed and the keyframe and make alignment marks for front to
back positioning using a sharp pencil. Do this at both ends of the keyboard. (See Ill. 3)
•You now have the ability to easily position the keyframe on the keybed whenever that is needed
during the process of installing a PianoDisc system in this piano.
D. Measure key height.
Illustration 4 - Measuring key height
E. Front Key Height.
•Key height is an important measurement that must be taken at this point. (See Ill. 4)
•Later you may need to set the height of the keys back to their original height.
•Use a ruler to measure from the top of the keytop to the top of the keybed.

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F. Remove the action from the action cavity.
•With your hand vertical and the guide pins between your fingers, pull the action from the action
cavity and place it on a workbench.
•If the piano arrives at your workshop on its side the action is nearly impossible to remove because
the hammers are rotated up from the rest cushions. To solve this, you will need to tilt the piano in
order to remove the action from the piano. Use a rubber mallet to tap on the keybed to help
hammer settle to their rest position.
•New pianos shipped in a crate usually have the hammers tied down. If this is the case you can
remove the action from the action compartment while the piano is still on its side.
Illustration 5 - Measuring key height – back
G. Back Key Height.
•You will need this measurement later on to calculate the length of the solenoid plunger.
•Use a ruler to measure the distance between the bottom of the key and the keybed. Do this at the
end of each section of the piano. Likely you will see variance in these numbers. (See Ill. 5)

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Illustration 6 - Sostenuto hook Illustration 6a – Draw line for reference
H. Mark the Center location of the sostenuto hook on the keybed and reference line at action stop.
•Disconnect the sostenuto pitman from the sostenuto hook.
•Use a 6” (15cm) rule to find the center of the sostenuto hook.
•With the square transfer this mark to the keybed. (See Ill. 6)
•Draw a reference line at the keyframe stop to locate keyframe to keybed for later use. (See Ill. 6a)
I. Lid removal.
•It is optional as to whether or not you remove the lid.
•Tape the hinge pins to the appropriate hinge to ensure that the hinge pins do not get lost during
the installation.
•If you remove the lid, as with the other case parts, store in a safe location and in a safe manner so
no damage will result.
•If you leave the lid on the piano secure the lid with a rubber band or soft cotton rope so it cannot
fall.
Illustration 7 - Piano on side

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J. Place the piano on its side.
•At this point, place the piano on a skid.
Illustration 8 – Outline leg on keybed Illustration 8A – Mark leg location
K. Mark leg locations on the keybed and legs.
•With the piano on its side, use a pencil to draw the outline of the left and right legs.
•On the top of each leg mark the location on the piano. (See Ill. 8A)
oustomarily, the bass keybed leg is #1, the treble keybed leg is #2 and the leg under the bass
bridge is #3.
•This information will be indispensable later when portions of the legs will likely be cut away.
2. Remove the keybed (if possible).
A. Determine if keybed removal is possible.
•If possible, the job of installing a PianoDisc system is much easier if the piano allows you to remove
the keybed from the instrument.
•Many, but by no means all, newer pianos allow removal of the keybed. A number of older pianos,
as well as all Steinway pianos, do not.
B. Check Appendix A of this manual.
•Appendix A, page 72 of this manual contains a list of piano makes with easily removable keybeds.
•While PianoDisc has tried to help you out here, this list cannot possibly be all inclusive.
•However, if the piano you are working on is not on the list the keybed may still be removable.
C. If in doubt, check to see if the keybed is glued onto the rim and belly rail.
•If the keybed is not glued to the rim and belly rail you will be able to remove the keybed.
•If you find that the keybed is removable do so. Otherwise you will be working inside the action
compartment rather than on the bench. On the bench is much more convenient and sensible if
possible.
D. Set up locating pins for the keybed.
•heck to see if the manufacturer included position pins. (See Ill. 9)
oIt is important to get the keybed back to its original location.
oAlso, with the pins in place, it is much easier to remove and install the keybed.

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oWhen you remove the keybed screws the locating pins will keep the keybed from falling until
you are ready to physically move the keybed to a bench.
Illustration 9 - M&H locating pin Illustration 10 – PianoDisc stainless steel locating pin
•Locate the PianoDisc stainless steel positioning pins in the kit. (See Ill. 10)
oThe pin is sturdy and because it is made from stainless steel will not corrode.
•Mark for two locating pins.
oPianoDisc prefers location pins at the end of the arms.
•Note: Drilling the holes for the locating pins is a two-step process. The hole in the rim or the belly
rail needs to be an interference fit, that is, the hole should be smaller than the pin by about 1/64”
(.4mm). The hole in the keybed should be larger than the hole in the rim or belly rail, about the
actual size of the pin.
Illustration 11 - Wood drill guide Illustration 12 – Store bought drill guide
•Drill the hole in the rim or belly rail.
ohoose a drill bit about 1/64” (.4mm) smaller than the pin you intend to use.
oDrill through the keybed so that the hole in the rim is about 1-1/2”(40mm) deep.
oMake sure you drill in a true vertical to the keybed surface because angled pins will make your
life quite difficult when removing and re-installing the keybed.
oUse a drill guide to drill a straight hole. (See Ill. 11 and 12)

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•Drill the clearance hole in the keybed.
oMeasure the thickness of the keybed.
oSelect a drill bit as close to the actual size of the locating pin.
oTape a flag on the drill bit so that the depth you drill corresponds to the thickness of the
keybed.
•Drive the location pin into the hole until it is flush with the keybed.
oWhen pounding in a locating pin it is important to not mushroom the head of the pin.
oTo this end use a hammer that is softer than the pin.
A good choice is a brass or plastic hammer.
E. Remove the keybed.
•Prepare saw horses, or some other support, on which to put the keybed after you remove it from
the piano.
•Remember that the edges of the keybed are finished so be careful.
•Remove the screws holding the keybed onto the piano.
•Lift the keybed off the locating pins and place the keybed upside down on the saw horses.
oA rubber mallet may be necessary.
Illustration 13 - Belly rail with pin
Illustration 14 - Mark shift lever blocks on keybed

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F. Mark the location of the shift lever support blocks on the keybed.
•Draw a line around the blocks that support the shift lever. Later on you will use these lines to
decide if you need to move the pedal lyre forward. (See Ill. 14)
•PianoDisc supplies optional metal shift lever bracket kit that can eliminate or minimize the moving
of the shift lever and lyre. Not all pianos need this but nice to have on hand. (Not supplied in kit.)
oThe shift lever kit # 5650-21025 ($15.00)
Illustration 14A Shift Lever Kit Illustration 14B - Shift Lever Brackets Installed
Illustration 15 - Draw line around keybed log Illustration 16 - Mark Sostenuto pitman hole
G. Mark the location of the keybed log on the keybed.
•Draw a line around the keybed log on the keybed. This will allow you to move the lyre and keybed
log a specific distance forward later on if needed. (See Ill. 15)
H. Remove trapwork.
•Remove all pedal trapwork from the bottom of the keybed.
•Mark a line 3” (76mm) forward from the center of the shift lever hole as a reference. Be very
accurate with this measurement. At the 3” (76mm) location place an intersecting line. (See Ill. 16)
oThis is an important step as the hole for the shift lever may be removed by the key solenoid slot
cut.

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I. Measure and mark Sostenuto pitman hole on the keybed.
•Draw a line perpendicular to the front of the keybed through the center of the sostenuto pitman
hole for future reference. It is best to place this reference line on the bottom of the keybed.
•It is not necessary to reference the location of the sustain hole as this will be determined by the
sustain pedal solenoid location later.
J. Remove the action stack from the keyboard.
•Remove the top action screws and store the top action in a safe place.
3. Measure for key access
A. Determine if you must omit key solenoids.
•Typically, at the high and low ends of the piano, the PianoDisc unit will extend under the legs. To
create the necessary room, some portion of the leg is cut away. Sometimes the customer objects
or perhaps there are very high value custom art case legs. For whatever reason, if you are not able
to cut the legs down for room, then you will need to omit key solenoids. It is no problem to drop 2
or 3 solenoids at each end of the piano. You will need to measure how far the leg protrudes under
the keys and drop key solenoids accordingly so that the slot the PianoDisc system no longer
extends under the legs.
Figure 1A

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Figure 1B
•Sometimes the leg mounting system doesn’t allow removal of material from the legs. A number of
pianos attach the legs to the keybed with bolts that go through the leg top into metal plates
embedded into the keybed. These plates cannot fall in the slot for solenoids otherwise you will
lose one of the legs attachment points. In this case you will need to omit solenoids so as to keep
the slot for the PianoDisc unit safely outside the leg mounting points.
•Use the following steps to determine your course of action.
In the piano
oMeasure from the Action Stop Block (on bass end) to the treble side of the Leg Bolt Plate. This
measurement should be taken parallel to the front of the keybed. This is measurement “X” in
Figure 1A. Transfer this measurement to the keyframe. See Figure 1B.
oMeasure from the Action Stop Block to the bass side of the treble Leg Bolt Plate. Again this
measurement should be taken parallel to the front of the keybed. This is measurement “Y” in
Figure 1A. Transfer this measurement to the keyframe. See Figure 1B.
NOTE: There must be 5/8” (16mm) from the side of the end key to the end of the solenoid slot for
key solenoid access.
Keybed off the piano
oMark a line on the keybed at each end of the slot. Same procedure as above - just be sure to
locate keyframe side to side before deciding notes to be left out.
Place the keyframe on the keybed at the locating marks made earlier in step 1-C. (see below)

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Mark the keyframe for the number of notes that will be left off each end of the solenoid tray.
B. Making the key stick.
•At the front of the keys, notes are evenly spaced from left (bass) to right (treble). Typically notes
are numbered starting at 1 in the bass to 88 in the treble.
Note: There are pianos that have more than 88 notes but the PianoDisc system only recognizes 1 88.
Illustration 17 - action Sections
•The back of the keys are divided into sections that correspond to plate bars in the piano. Often,
but not always, there will be 4 sections. The bass is group 1, the tenor is group 2 (sometimes there
are two tenor sections), the low treble is group 3 and the high treble is group 4. The spaces
between these groups are referred to as breaks.

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C. Decide how to deal with sections that have an odd number of notes.
Illustration 18 – PD Standard PD systems Illustration 19 – PD low profile solenoid
Illustration 20 – PD low profile solenoid rail systems
•There are important differences between the Low Profile PianoDisc System and the standard kit.
The LP system has two rows of solenoids instead of one. The row closest to the capstans is
referred to as front. The row closest to the end of the keys is referred to as back.
•Each solenoid bracket assembly mounts two solenoids. The bracket is designed so one end
mounts on the front mounting rail and the other (slot side) mounts on the back mounting rail. The
bracket positions the solenoids in two rows between the two mounting rails.
•The bracket is designed to be mounted at an angle so that the solenoid on the front rail falls under
one key and the solenoid on the back rail falls under the next note higher in the piano. It is not
possible to mount the bracket at the opposite angle.

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•An important consideration to keep in mind is that it is important to keep the length of the slot in
the keybed as short as possible. Among other reasons this minimizes the clearance cuts in the legs
that will be required. To this end, solenoid bracket assemblies need to be mounted so that the
end solenoid falls on the end key at the top and bottom of the scale.
•At the lowest note in the piano, usually note #1, this presents no problem as the solenoid for note
1 is the front solenoid and the solenoid for note 2 is on the back solenoid. All you need to do is
mount the bracket at the appropriate angle and everything will work.
•At note 88, if there is an even number of notes in the section, there will be no problem as the last
solenoid (the back solenoid) will fall on note 88.
•If you have omitted solenoids then the highest and lowest note numbers are where you will need
to start numbering for the PD system.
•Not all sections have an even number of notes. If the note count is not even then the approach
needs to be different. There are no single solenoid brackets, they all provide two solenoids. This
means that in a section with an odd number of notes there will be one extra solenoid. If the front
solenoid were to fall on note 88 the extra solenoid would fall on the non-existent note 89. This
would require extra room in the slot and more material removed from the leg. While the system
would likely work this is not a good idea.
Illustration 21 – Direction of solenoid Illustration 21A - extra solenoid in break
NOTE: Pictures above is ONLY for a reference – DO NOT assemble solenoid rails until instructed.
•It is better to match solenoids to keys in the high treble starting from note 88 and working down in
the section. The extra solenoid will then fall in the break between the low treble and high treble.
It is ok to have a back solenoid on say note 72 and a front solenoid in the break. (See Ill. 21A)
ustomarily, for any solenoid that will not operate a note you will simply cut the wire and remove
the plunger. The kit will always provide spares so there will always be enough.
•ount the notes in each section. For those sections with an odd number of notes, decide where
the extra solenoids will be placed. Once you have made these decisions you are ready to make a
key scale stick.
NOTE: It may be necessary to omit a solenoid (at the starting point) if there is an odd number in the bass
because of the sostenuto in the break area. This will mean that you would start with second key.

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D. Make a scale stick from the back of the keys.
•You will need a stick of wood that is about 2” (50mm) longer than the distance from the outside of
note 1 to the outside of note 88. This stick should be about ¼” (6mm) thick. The dimensions for
length and thickness do not need to be precise.
•The width of the key scale stick should be 9/16” (14mm) because this is the available space
between the solenoid rows when the diameter of the stems is taken into account. It is important
to be reasonably accurate when cutting the width of the key scale stick otherwise there will not be
ample room to space the solenoids apart.
Illustration 22 - Marking scale stick
•Place the blank key scale stick on the back of the key approximately 3/8” (10mm) in from the back
of the key. Tape the strip onto the keys so it is not able to move. Mark the bass end of the key
scale stick so you do not accidently set up the solenoids backwards later. (See Ill. 22)
•Mark the strip with a sharp pencil, on alternating sides, where the scale stick intersects the center
of the key. Start at note 1 in the bass. Remember that when working on the back of the keys the
bass keys are to your right. Mark note 1 on the front side of the strip, mark note 2 on the back
side of the strip. (See Ill. 22) Mark all 88 notes in the piano in this fashion.
4. Measuring for keyframe cut
A. Remove the keys from the keyframe.
•Remove all keys from the keyframe except the end keys in each section.
•It is best to store them in order 1 to 88 as it makes re-assembly much easier.
•If the numbers on the keys are not easy to read, re-number the keys with a ball point pen behind
the capstans so that the numbers do not show after the action is attached to the keyboard.

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Illustration 23 – Marking keyframe cut location Illustration 23A – Rubber band for punchings
NOTE: When measuring to cut the key rest felt, if most of the felt will be cut away or there is no loose
felt, just the glued on portion, then you should carefully remove the felt and re locate forward to the cut
line. Use a sharp chisel to remove the felt. It will be necessary to re level keys later.
B. Mark the back rail cloth for the keyframe cut.
•Measure from the end of the first and last key in each section 1.5” (40mm) towards the front of the
key. (See Ill. 23)
•Place a mark on the keyframe felt.
•This dimension will leave the keyframe hanging over in the slot area 11/16” (18mm). (See Ill. 24)
•The clearance from the keyframe to the front solenoid row will be about 3/8” (10mm).
•The purpose of this approach is to preserve as much of the keyframe as possible.
•Mark a straight line from the points with a straight edge.
•Use a lid rubber band to secure the balance and front rail punchings from falling off while the
keyframe is inverted. (See Ill. 23A)
oWeave the rubber band thru the front and balance rail pins for this purpose.
C. Mark the bottom of the back rail for the keyframe cut.
NOTE: The purpose of marking the keyframe cut line on the bottom of the keyframe is to see if there is
support or not. The keyframe is cut from the top side.

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Illustration 24 – Keyframe/bed side profile Illustration 25 - Bottom of keyframe
•Turn the keyframe upside down.
•Measure, from the end of the #1 and #88 keys, towards the front of the keys, 1.5” (40mm) and
mark on the bottom of the keyframe. (See Ill. 24 and 25)
•This is the keyframe cut line.
NOTE: If less that 2” (50mm) width of rest rail is left, after keyframe cut, it is recommended that some
Re enforcement is added to the front of the rest rail before cutting the keyframe. You can
actually use the piece of wood cut for the re enforcement.
•Measure, from the end of the #1 and #88 keys, towards the front of the keys 2-5/16” (58mm).
•Mark this dimension on the bottom of the keyframe for the bead or keyframe support.
•Draw a line the length of the keyframe from key 1 to 88. (See Ill. 25)
•This line represents the front of the keybed slot.
NOTE: It may be necessary to extend the shift lever contact point on the keyframe. (See Addendum 2,
page 78)
D. Determine if the back rail needs additional support after it is cut back to the required dimension.
Illustration 26 – Keyframe without support bead Illustration 27 – Iron-on veneer shim