P.S. Don't forget to have plate washers with you. I theorize that the reason the agraffe broke in the first place was that people in a hurry in the factory muscled it into line when it had already bottomed out, instead of turning it out and shimming with a plate washer. The strain just stays there for thirty or forty years, and then the brass has had enough of it. The pianos where I've had to do this repair have dated from the 70's. Hopefully this doesn't happen any more. In a pinch once, I just cut a little doughnut of business card to shim the agraffe so that it would line up perpendicular to the string. Oddly enough, that worked okay.
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