> I am tempted to pull the whippen rail backwards, but its already back as far as the screwholes will allow. Could always enlargen the holes but.... You can shim a flange so it moves back a bit. Take careful measurement of up and down weights before and after the move. The set of measurements that have the smallest difference between up and down is the superior alignment. Take real accurate measurements of spread action before moving the rail. If you look at the cross section of the Yamaha action rails you will realize that their configuration is extremely resistant to flexing. The very best way to bed a key frame is to remove the stack, remove the keys, replace the stack and make sure the screws hold the frame securely at all screws. Because of the angled screws in the front of the stack they should be the first loosened and the last tightened. They are intended to act as toe nails do, preventing any movement after being secured. If someone tightened the screws improperly then the action can be bound. Replace the action in the action box and turn all the studs up so they all are off the keybed. Starting at the center turn each down so that a piece of newspaper or other thin paper can be pulled out from under every stud with a little resistance. This provides about .005" clearance between the stud and the keybed but this will be closed very securely be the weight of the keys. The stack can warp the keyframe a little which can throw off bedding without the stack. With the keys out of the way you can check all three rails as the process goes on. Don't forget the hidden stud! Replace the keys and you will have the best possible bedding for that keyframe and that keybed. If you find any warpage in the keyframe you will need to correct that by making saw cuts in the frame in a shallow ^ form and cut wedges to fit the cuts. To warp a key from down you will make the cuts underneath the rail and drive the wedge in until the frame comes down. Yamaha has these cuts already in the front rail. They are driven in tight and the frame planed to a curve. The wedge is glued in on one side only so they are easy to remove. Cut a wedge to match the old and tap it into place until you have the mating you wish. You have received the benefit of several hundred man years of experience and knowledge. Have a hard look at what the situation is then do nothing that you cannot immediately undo. Solve the problem so another technician won't ask, "Who the hell did this butcher job?". If you make substantial (2 or more mm) changes in spread action you will need to concern yourself with touch weight and reweighing the action. That is small compared to getting an action to function properly. Lots of luck. Newton
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