Well here’s the image I promised y’all. The problem was the damper tray would not fall on it’s own away from the underlevers when even the slightest of hindrance was present after installing the PianoDisc player system. The result initially was the bass dampers were leaking (singing, ciphering). I readjusted almost the entire bass section and the result was the problem moved to the top quarter of all the dampers then leaked. Rather than chase each leaky damper only to have new ones show up, and to prevent the eventual and occasional leaker show up as damper felts compress with time, I considered many other alternatives the least desirable being a total redesign of my pedal mechanism cross over, pedal solenoid placement and pedal push rod interface. A time effective, cost effective and viable fix was to increase the downward weight of the damper tray. Some piano manufacturers have used a damper tray return spring as part of their usual production run. My previous post indicated the lack of return even though the pitman was removed. I tried lubing the damper tray pivots and felt there was no change which led me to believe the underlever flanges were sluggish. (the piano sat in storage for a while) For the damper tray to drop away from the underlevers once the damper felts are resting on the strings, all of the underlever flanges must move. Additive friction is creating my problem along with the usual friction points associated with the entire pedal assembly and it’s design. I could have lubed all the underlever flanges but that fix has historically been temporary ... not that I’ve experienced that with Protech CLP which is what I considered using however, I didn’t go that route. I could have repinned all the underlever flanges but that requires lots of time. All of these methods mentioned added together would have taken me two days to complete. I opted to install a very simple fix that cured all ills and when weighed against all the parameters involved with this job, I felt it was the best choice. Mind you I’m not responsible for the condition of the piano when it arrives. A dealer appreciates a cost effective and reliable job. As long as the customer is happy with the results there’s no need to impose any additional expense on all involved. I feel the true art of our trade is to master this balance with knowledge and ingenuity. I wound 22 gauge piano wire around a half inch dowel pinching the wire and the dowel in the jaws of the vise. I then made two rounds and cut it off with plenty to spare at each end. I then made the trip to the dealer’s floor and drilled two holes just big enough to accommodate the wire and about an inch (25 mm) deep or better. The final fitting was done on site including the right angle bend where the wire goes into the damper tray. To make the wire even tighter in the pivot block hole, I put a few small bends in the wire distorting it slightly. The other end has to rotate slightly in the hole so I left it free to move. The inherent shape of the spring coupled together with the force it creates keeps the wire in position and therefore no glue was used. Using a very slow release to reduce the effects of inertia, I adjusted the spring until the damper tray followed the rest of the mechanism away from the underlevers and then I made it just a hair stronger. This adjustment was made just outside of the pivot block. You can see the wire bend just outside of the block in this image. Considering the zillions of times this tray moves, I included the loops to spread out the fatiguing effects over a larger portion of the wire. The loops also absorb the discrepancy between the two different radii of the damper tray pivot and the spring. I was in and out in about an hour, the dealer was happy, and I had ample time to join a pretty pair of blue eyes for lunch. She’s a good low fat cook. Hmmmm. -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20130218/4f76abf7/attachment-0001.htm> -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: image/jpeg Size: 66554 bytes Desc: not available URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20130218/4f76abf7/attachment-0001.jpeg>
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