QRS Music Technologies PMII, Installation Manual, Page: 13 / 52

Installa on Procedure
13
July 2013
Modifying the Keyframe ‐ Grand...
If you are installing a QRS PNOscan II record system you should incorporate it’s installa on while modifying the pi ‐
ano ac on. The PNOscan II has it’s own installa on manual.
The Keyframe will probably require modi fi ca on to accommodate the Key Solenoid Rail Assembly. The key tails must
protrude over the back of the ac on frame, so the rear of the key frame must be cut away.
Tools needed for this chapter: pencil, paper, wood chisel, straightedge, jig saw, palm sander & sand paper, u lity knife,
wood glue and an assortment of screwdrivers.
At this point in the installa on, the piano is on its legs, the fall board, keyslip, and cheek blocks have been removed,
and the lyre is s ll in place. The piano has been measured to verify that the Note Rail Assembly will fi t.
Measure the distance the ac on shi s when the le (una corda) pedal is pressed. (If a hammer li rail is installed,
measure the distance the hammers li for a given movement of the so pedal lyre li rod.) Measure the distance the
so shi (una corda) pedal li rod travels when the pedal is depressed. Write these measurements down for later
trapwork installa on.
Remove the en re grand or upright piano ac on from the piano and place it on a clean, level workbench. Do not de ‐
press the keys while sliding the ac on in or out of the piano, or broken hammers will result.
Examine the rela onships of the key tails to the rear edge of the keyframe. Each key tail must have at least 1 ‐ 1/4" ex ‐
posed beyond the rear edge of the key frame. If this is not the case, then the key frame must be modi fi ed. If modi fi ca ‐
ons are required, follow these steps:
IMPORTANT : Before removing the hammer ac on from the key frame ac on you must fi rst measure the distance
from the bo om of the key frame ac on to the bo om of the piano key. Next, depress the key and measure once
again, from the bo om of the key frame ac on to the bo om of the key. Write these measurements down for later
use.
With a screwdriver remove the wooden key stop rail from the key frame.
With a screwdriver remove the hammer ac on from the keyframe, being certain to note any screw length di ff erences
in the 8 or 10 wood screws used to secure the ac on to the keyframe. It is always advisable to put the same screw into
the same hole.
Verify that the keys are properly numbered before removing them. Remove all keys except key numbers 5, 84, and the
break keys. With a pencil, mark 1 ‐ 1/4" in from the ends of the key tails onto the keyframe. Allow an addi onal 1/4" at
either end of each sec on. With a straightedge to guide you, connect the marks in each sec on. Removal of the back
rail felt may be required before this step. (Figure 1)
The back rail felt rests beneath the key tails, and can be removed by using a sharp u lity knife or in some cases a wood
chisel. Place the removed back rail felt to the side for future use when reloca ng and re ‐ gluing in its new posi on.