Benjamin Treuhaft wrote: > An 1890's Steinway upright action is sluggish due to verdegris. I >flooded all the centers with Renewsit, the stuff Franz Mohr used for >years to free seized centers. I massaged it in, sliding the center >pins back and forth. That worked for a while. > It came back. > Next, I wet all the centers with alcohol and water and hit the >action with heat from a hair dryer. That worked fine. > It came back. > Finally, I repinned dozens of centers, washing out the bushings >with Renewsit before and during reaming. It worked great. > It's back again. What shall I do? >Ben Treuhaft >Berkeley, Calif. >ps Next week I'm going to install a dampp-chaser and control unit. The green stuff is enough of a problem that I know better than to suggest that there is a solution that works in all instances (other than parts replacement). There are degrees of the problem, some pianos have it worse than others, and I also suspect that previous treatments by other techs in the past could affect the results of anything we do in the present. My own M has a mild case of the green. Years ago I treated the centers with silicone and naptha. This action plays well, and I actually consider the green stuff a very positive factor in this piano because it seems to have kept the friction of the centers up to good levels, not allowing the centers to get loose. I was once called to work on an M that was bound-up and unplayable. I applied Protek and although there was some improvement, many centers remained sluggish. In desperation, I applied silicone and naptha to all the centers in addition to the Protek that I had just put on. I was very worried that the combination of the two might have a bad effect due to some unknown unpredictable reaction between materials that are not normally mixed, but these action parts were worthless the way they were, so I took the risk. The results were good and immediate. The action freed up. The next time I saw this piano it was still performing well, with only a couple sluggish centers. I am not recommending this procedure, but simply reporting that it seemed to work for me in one specific case. Kent Swafford
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