My sadly vague memory is that the various jigs held firm and supported the parts of the bichord damper which weren't being cut so they couldn't squirm out of the way. Paul had an extremely sharp knife which he touched up frequently.
It would cut one of the four needed faces, then the damper could be reversed in the jig or put in another jig, and he could cut one of the others. The cuts were straight, so the grooves for the two halves of the bichord started as v-shaped. Being installed turned them to the curved shapes, just like monochord dampers.
Also, it was only the bottom part of the bichord section which has these "double-bump" dampers. They are for the larger sizes of bichords.
I have a vague memory of someone in Colorado having learned the procedure and made some jigs? A source for the firm bass damper felt was needed.
Original Message:
Sent: 9/12/2021 6:15:00 AM
From: Robert Edwardsen
Subject: RE: M & H Bi-chord dampers
Paul planned to donate these jigs to the PTG museum. Perhaps you could get examine them there or maybe someone could send you some pictures of them.
Robert B Edwardsen
Registered Piano Technician
21 Courtenay Circle
Pittsford NY 14534
585-586-1360
edwardsenpianoservice.com
eedward2@rochester.rr.com
Sent from my HAL 9000
Original Message:
Sent: 9/11/2021 7:05:00 PM
From: Susan Kline
Subject: RE: M & H Bi-chord dampers
Paul Monachino used to give a class demonstrating how they can be made. He hung around M&H as a kid after Aeolian took it over, but while the old techs were still working there. As they retired them gave him their jigs. Each person had to make their own jigs back then.
It was ingenious but not that difficult to do. You'd need to get the right density of bass damper felt, and to make the jigs. Someone probably still knows how to do it.
Original Message:
Sent: 9/11/2021 2:35:00 PM
From: Ron Bergeron
Subject: M & H Bi-chord dampers
1922 Mason & Hamlin A has these wonderful bi-chord damper felts. Does anyone know where replacements like this can be found?
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Ron Bergeron, RPT
Austin, Texas
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