Yes, the placement of the spring is a consideration. Steinway has a spring mounted in the tray. With a PianoDisc installation, all the original trap work for the sustain pedal and the sostenuto pedal are redesigned as part of a normal installation. I considered numerous locations on this one and in the past I’ve installed a coiled spring between the keybed and the crossover (trap lever) near the pivots on the pitman side of the pivots when needed. This one didn’t have that space available due to the 1 to 1 ratio and the position I chose to locate the pedal solenoid. The design of the pedal mechanism is developed with the piano on it’s side and so the effects of gravity and final function has to be dealt with after the piano is put back up on legs. Putting the spring in a primary function location (a position that presses the entire assembly together) is more efficient than in a secondary position (a position that pulls the assembly from one direction and presses the rest of the assembly towards the other direction). One could argue the same amount of force being applied in both cases but I like the simplistic and fundamental approach of providing all the force in one direction. It also, I feel, helps to keep the mechanism quiet during automatic play by gently pressing things together constantly. As it turned out, I had to swap the pivots for the sustain pedal for the sostenuto pedal in the pedal box to quiet the mechanism. It had the wooden dowel type of pivots than had worn so I not only swapped them with the lesser used middle pedal, but I turned them around so the outside unused part of the dowel was now next to the pedal. A nice snug fit made for a very quiet functioning pedaling system. The pinned part of the pitman was eliminated. What shows in the image is what’s been left behind. It now acts merely as a fence for the present pitman which is kept in place simply with a hole in the tray. I could have removed the “fence” but there was no need. Usually there’s a three holed guide for the pedal push rods on grands generally speaking, however this Baldwin model and a few other Baldwins have pinned push rods that mate up with bushed holes on the trapwork negating the need for the guide. This makes for an out of the ordinary player installation. Considering the pitman and the push rods are not “locked” in place, a spring that constantly compresses the entire assembly together just plain makes me feel better about the final design. I’ll be considering this same spring for future installs of this type. It’s so easy to make and install!! Some “current” production run Baldwins have a black rubber band holding the pedal push rod in the bushed hole on the lever. In the past I’ve duplicated this design with my player installs but it was prone to age related failure as the rubber ages plus the movers have one more thing to deal with when re-installing the pedals. Plus, even though I’ve glued one side of the rubber band to the piano’s trap work, there’s still a risk of the loss of the part in transit. I feel this design (damper tray spring) alleviates numerous tendencies towards failure hence my enthusiasm to share my idea with other possible player installers or technicians with related issues in the field. If the tray pivot is inline with the flange centers and there are underlever assist springs, the springs cause the tray to rotate causing damper leakage. One solution is to place a coil spring between the belly and the tray. Or, since the pitman is pinned to the tray and trapwork, you could put a spring on the trap lever to pull the tray down. -- Regards, Jon Page -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20130219/847d5002/attachment.htm>
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