If you use the following multipliers on the speaking lengths to calculate the distance the hammers must be from a properly V-shaped V-bar, you won't have to worry about "correcting" your treble strike line.
(note88 .064), (note83 .075) (note78 .085), (note73 .089), (note68 .094)
I use a 20" disc sander to taper the sides with a vacuum cleaner attached to catch (some) of the dust. Very powerful, dangerous machine. One must have a most delicate touch and if you don't have it, I don't suggest the tool. 80 grit Aluminum oxide abrasive. If one uses minimal pressure against the disc, (which you should to be safe), even hammers with lacquer in them can come out clean looking. If your work piece begins to vibrate, LET GO OF IT BY PULLING YOUR HANDS BACK IMMEDIATELY. No loose clothing! No neck scarves!
The old style tone regulators at Steinway had a two blocks to hold the hammer while planing. One block was for first side taper, the pother for second.
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Edward McMorrow
Edmonds WA
425-299-3431
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Original Message:
Sent: 03-12-2018 09:56
From: Jim Ialeggio
Subject: Belt or Disc sanding hammer tapers
Thus enter WNG shanks which are significantly smaller diameter than wood.
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Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
Original Message:
Sent: 03-11-2018 23:09
From: William Ballard
Subject: Belt or Disc sanding hammer tapers
Bear in mind that in the area around the hammer bore, the molding can't get too thin, or you might not be able to break the glue joint and remove the head if you need to.
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William Ballard RPT
WBPS
Saxtons River VT
802-869-9107
"Our lives contain a thousand springs
and dies if one be gone
Strange that a harp of a thousand strings
should keep in tune so long."
...........Dr. Watts, "The Continental Harmony,1774
+++++++++++++++++++++
Original Message:
Sent: 03-08-2018 10:58
From: David Love
Subject: Belt or Disc sanding hammer tapers
I use the table saw method as well. When I have a hammer where I need to take off more, even after it's been hung, I use a plane secured in a bench vise (see attachment). Pull stroke sometimes works better than a push stroke. When pushing I use a notched piece of wood or dowel to spare shaving off parts of my fingers. But if the plane is sharp you can just drag it across while holding both in hour hands. You can be very precise and shave off from either the felted area or the tail. There won't be any staining. The hammer molding does have a grain and usually it cuts better in one direction than the other. You can do the whole set that way if you want. Easier than sanding by hand, I think--and less messy.
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David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
Original Message:
Sent: 03-07-2018 08:39
From: Jim Ialeggio
Subject: Belt or Disc sanding hammer tapers
To adjust hammer weights to my targets, prior to hanging, I taper on a Spurlock type setup, using a good sharp Forrest table saw blade for the cuts. I like my system and its a real clean cut. However, occasionally, as taper adjustments get the biggest bang for weight changes, I want to go back to an already cut taper and remove more. A second machine/jig pass on an already tapered hammer difficult to do and set up, for a single hammer...so I don't re-taper, on my Spurlock type setup.
The easy way to adjust an already tapered hammer, would be to take it to the stationary belt sander (6x48) and eyeball it. My problem with sanding this way, is that is stains and mucks up the felt. I have tried 50 grit blue alumina zirconia belts, 100 grit dark brown aluminum oxide. Both make a real mess of the hammer. The 100 grit is worse than the 50 grit, as it runs much hotter, I think. How do those of you who use sanders for tapering avoid gumming up and staining the hammer side?
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Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
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