Jim, I assume you have the type action where there is a continuous brass flange anchoring a whole section of hammer butts; each individual boss on the flange has an unthreaded hole, with a butt plate (threaded hole) facing the player and the screw head facing the strings. For purposes of my explanation, please note the following nomenclature: A hammer butt is the shaped wood piece at the bottom of the hammer shank, a butt plate is the small brass piece with the hole in it. Usually, if the butt plate or brass flange is cracked, there will be a click as the note is played and a rattle as the assembly returns to rest; if the hammer rest felt is hard from age, the hammer shank may "sing" a bit as it hits the felt. In my experience, wobbly hammers on this type of action may come from -- in descending order of frequency: 1. Butt plate cracked at screw hole 2. Brass flange cracked at the center pin groove 3. Worn bushings in the hammer butt; either repin or if the bushing is too far gone, rebush. 4. The bushing hole (which comes close to the edge of the wood) is cracked. I have had good experience with thin CA glue here, but of course the better repair is to replace the hammer butt. 5. Loose screw. If have found this sometimes. 6. Hammer shank loose in butt I always take the damper flange loose to get at the butt plate screw. I loosen the butt plate screw just enough to slip the center pin out and remove the hammer butt. I put my finger in behind the butt plate and feel to see if it is still flat or if it has gone swaybacked. If swaybacked, I remove and replace with a new one, checking to see that it does not rub on the hammer butt when that is reinstalled. If the butt plate is not cracked, I look at the boss or nub on the brass flange and there is usually a slight crease showing where the flange is cracking at the center pin groove. Sometimes pulling on it with index finger will pull it loose. This means installing a repair clip. Installing a repair clip means some extra filing and fitting and a dab of glue to make everything line up and stay lined up. Email me if you need any help with this. As a check whether the hammer wobbles from a loose center pin, I grasp the center pin with a pair of pliers while I have the hammer out, and check to see if the pin moves around in the bushing while I pull the hammer side to side. Bill Maxim, RPT In a message dated 98-06-12 23:24:58 EDT, you write: << I installed new butts and hammers on a Kroehler upright. I have checked the brass rail and the brass butts where the screw goes in. This is the type where the screw goes through the rail and then the brass butt receives the threaded screw. The butts have been replaced where hammers have loosened but the problem continues. When it seems I have solved the problem, another hammer loosens. As near as I can tell the rail is not cracked. If anyone has had experience with this problem I will certainly appreciate advice. Jim Dally >>
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