Greetings, I have been blessed with a pair of Steinway uprights, (Stella and Eleanor, we named them after the widows that sold them to us), of the # 70213 vintage, and remember some of the things that made them go so well. One of the most critical dimensions I found was the thickness of the butt leather. There is a very short moment arm between the butt flange center and the jack's contact point. Reducing the thickness here makes a dramatic increase in weight, (though you can develope a lot of initial velocity!!). If your centers are in the ball park, try bringing the jack out with shims under the leather,until you find a point of failure. See if there is not a range of touch-weight that is displayed as the thickness changes. You are right, these old, large Steinways are really great instruments, and with a good action, will play along with the best. Their soundboards seem to be especially durable. Regards, Ed Foote
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