>..Dear List: > >..i have in my posession a DH Baldwin action..customer is correct when she >says the action is *heavy*..bass section feels like there's concrete on the >back of the keys..tenor and treble section feels fine..i backed the jack off >of A0 till it missed and then reset it..still feels heavy.. > >..suggestions warmly welcomed.. When presented with a piano which exhibits an excessively heavy touch as you describe I prefer to start with the basics. Heavy, unresponsive touch? Suspect excess friction...somewhere. Several years back there were some timely articles in the Journal concerning the evaluation of friction and weight in the action. With a simple set of accurately calibrated gram weights, you may measure downweight and upweight on selected keys (without the weight of the dampers). Subtract upweight from downweight and divide by 2 to determine frictional resistance (12 - 15 grams should be ok). Add upweight and downweight and divide by 2 to determine weight resistance (35 - 40 grams should be ok). These basic measurements will quickly determine whether the action is suffering from excess friction, weight or both. David Stanwood (may we call him the touch weight guru?) has taken this analysis a quantum leap forward with his new touch weight metrology but I'll leave that discussion for him or someone else more qualified than I to continue. You may choose to assume that there may be excess friction in this action and simply proceed from the front of the key to the top of the action to examine all the friction points and ease and/or lubricate where necessary. Protek works on keypins, capstans, jack tips and repetition levers; micro-teflon powder works very well on whippen cushions and knuckles (even keybushings if you want to be fussy). Remember to check the balance hole on the keys for proper fit and ease if necessary with the tapered tool inserted through the key button. Of course, tight action centers (particularly the hammer shank flange centers) are another common cause of excess friction and may either be treated with Protek or repinned where appropriate. If there is excess weight in the action, particularly the bass section, you may choose to remove some mass from the hammer moldings (by tapering the sides of the hammer). As there is roughly a 5 to 1 ratio from the tip of the key to the tip of the hammer, removing 1 gram of weight from the hammer molding results in a 5 gram reduction in the down and upweight measurements at the playing end of the key. Hope this helps, Stan Kroeker Registered Piano Technician Kroeker & Sons Piano Experts 59 Quiring Bay Winnipeg, Manitoba Canada R2G 1Y5 Ph. 204-669-5881 Res. 204-661-5621
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