Dear Friends, About a month ago I was doing a prep on an older Kawai KG-2A grand piano and tightened all of the bolts and screws on the piano. Just for fun I counted all of the screws and bolts I tightened, probably because I am compulsive! I realize this may be a big waste of your time, but I do have a few questions at the end. There are a bunch of screws on a grand piano! I think you could probably break it down into 3 categories. 1. Case (Pinblock, Plate, Bench, hinge and hardware screws and bolts. This would be all of the bolts and screws that are accessible without getting on your hands and knees or without opening up the action). 2. Action Screws (Action, keyframe, spring and action cavity screws. Including all screws accessible inside the action cavity). 3. Undercarriage Screws (Leg, Lyre, trapwork, etc. All of the bolts and screws underneath the piano) Here for your amazement and amusement is a list of the screws I tightened. 1. Case Bench - 4 bolts and 32 screws Music Desk - 62 screws Top Lid long hinge - 44 screws Lid log - 8 screws Side hinges on top lid - 18 screws Lid prop cups - 3 screws lid prop hardware - 4 screws Music desk guides (on inner rim of piano) - 6 screws Through plate into stretcher - 3 screws plate web - 23 screws plate perimeter - 7 screws 2. Action leg plates, spring, and key cover hardware - 25 screws key upstop rail - 4 screws Damper underlever flange - 69 screws Damper tray - 4 screws hammer flange - 88 screws wippen flange - 88 screws action brackets - 10 screws Action rails - 20 screws hammer rebound rail - 10 screws and nuts underside of keyframe - 17 screws 3.. Undercarriage Rear leg plate - 8 screws Lyre braces and lyre - 12 Trapwork - 12 screws Keybed - 22 screws leg and lyre bolts - 8 bolts keycover - 6 screws cheek blocks - 4 screws keyslip - 15 screws It makes sense to me that if I keep the screws tight it will benefit the piano by eliminating noise, improving tone and volume, keeping parts aligned and keeping the piano from falling apart. 1. How critical is it to tighten all of these screws? I would guess that on a concert grand, you would do all of this at least once a year, but for other pianos it may not be as important (unless the customer wants to pay for it). And on a Winter spinet it would never get done because the piano never gets tuned anyway, let alone any cleaning or tightening! 2. Does anyone keep track of this for the pianos you service? For a school with many pianos, it would be easy to forget which pianos you tightened and which pianos still need tightening. I am thinking of making a list of all the pianos and each time I tune, picking an area and tightening all the screws in one area, such as tightening all case screws. Then next time, I will see on the list that I need to tighten the action screws. And eventually all the undercarriage screws would be tightened. This would make sure that the work gets done on every piano on a rotating basis. Just rambling thoughts! Have a nice day David Vanderhoofven Registered Piano Technician
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