> This message is in MIME format. Since your mail reader does not understand
this format, some or all of this message may not be legible.
---------------------- multipart/alternative attachment
Hi David, Good suggestion. Here they are.
Alan
=20
ORIGINAL NUMBERS =20
NOTE A1 A#2 F9 F#10 C16 C#17 C28 C#29 C40 C#41 C52
C#53 C64 C#65 C76 C#77 B87 C88 AVG
D 69 67 65 70 69 69 64 68 65
63 57 60 58 57 71 79 63 67 65.6
U 40 37 34 36 38 41 43 38 41
41 36 35 39 37 48 47 44 46 40.1
F 14.5 15.0 15.5 17.0 15.5 14.0 10.5 15.0 12.0 11.=
0
10.5 12.5 9.5 10.0 11.5 16.0 9.5 10.5 12.8
BW 54.5 52.0 49.5 53.0 53.5 55.0 53.5 53.0 53.0 52.0
46.5 47.5 48.5 47.0 59.5 63.0 53.5 56.5 52.8
FW 41.0 41.6 40.7 37.4 37.0 37.2 25.6 30.5 25.0 26.9
24.2 24.2 15.6 18.1 1.9 1.5 -5.2 -8.6
SW 12.0 11.6 11.2 11.2 11.3 11.4 10.1 10.4 9.8 9.7
8.9 8.6 8.2 8.0 7.2 7.3 5.4 5.5
R 7.1 7.2 7.1 7.2 7.1 7.2 6.8 7.1 6.9
7.1 6.8 7.2 6.6 6.9 7.1 7.4 7.1 6.9 7.=
0
=20
NOTE KR WW WBW
16 0.56 18.1 10.14
17 0.56 18.0 10.08
40 0.57 18.2 10.37
41 0.56 18.2 10.19
64 0.56 18.5 10.36
65 0.56 17.7 9.91
AVERAGE WBW =3D 10.18
=20
KnuckleCore/CnterPin =3D 16.0
Capstan Convergence? No , Too low
Bass Action Spread: 4.438=B2
Treble Action Spread: 4.438=B2
> From: "David C. Stanwood" <stanwood@tiac.net>
> Reply-To: "College and University Technicians <caut@ptg.org>" <caut@ptg.o=
rg>
> Date: Tue, 26 Oct 2004 11:03:05 -0400
> To: <caut@ptg.org>
> Subject: [CAUT] Re: Moving Capstans
>=20
> Alan,
>=20
> I can't access your .xls file either...
> How about just giving us typed columns of numbers such as:
>=20
> N U D FW SW KR WW
>=20
> 16 25 50 28.0 10.4 0.52 18.5
> 17 25 50 28.0 10.4 0.52 18.5
> 40 25 50 28.0 10.4 0.52 18.5
> 41 25 50 28.0 10.4 0.52 18.5
> 64 25 50 28.0 10.4 0.52 18.5
> 65 25 50 28.0 10.4 0.52 18.5
>=20
> The above minimal sample notes give a good idea of what's going across th=
e
> keyboard.
>=20
> To answer your question: You can tell how far to move a capstan by looki=
ng
> at the Balance Weight. As a rule of thumb, for every decrease in BW by
> 1.0, the overall strike weight ratio will decrease by 0.1. If you have a
> ratio which is 6.0 and you want to achieve a 5.5 just plug in the numbers
> and solve the equation for BW:
>=20
> BW=3D(SWxR+WWxKR)-FW
>=20
> The result is your new target BW for making your desired strike weight ra=
tio.
>=20
> In the above samples the ratio calculates to 6.0 with a 44 BW.
> To make a 5.5 ratio the target BW is 39.
>=20
> When working with an existing heel cushion and a 90 degree capstan I do n=
ot
> recommend just moving the line but rather angling the capstan backwards a=
nd
> bringing the capstan line forward so that the capstan contact point on th=
e
> heel shifts forwards. For a small, medium, and large effect, try 4, 8, =
or
> 12 degrees. http://www.stanwoodpiano.com/CapRoll2.jpg
>=20
> Isaac says we are in a geometrical world. It's not that simple. Yes we
> have to pay attention to geometry but weight also has to be dealt
> with. Both are important for the pianist. In regards to weight, my
> formulas offer the clearest solutions.
>=20
> As for Geometry... follow the rules and make sure you can regulate it. I=
f
> you are going for lower weight ratio (5.0 - 5.8) expect to use a minimal
> blow distance of 44.5mm/1.75". If you move a capstan line, test the resu=
lt
> before committing to the new line. If the dip is too deep for a short bl=
ow
> distance then don't do it!
>=20
> As a recent example: Last week Tim Coates, from Sioux Fall South Dakota,
> was in my shop for PTD training and he brought a Steinway D action to wor=
k
> on. The strike weights were in the TopMedium range and he had tested the
> tone by increasing strike weight with the addition of binder clips on the
> shanks. Listening to the tone in the concert hall told him that 1/2 High
> SW zone (a normal concert hammer weight) would give best results...
>=20
> The average SW Ratio level was 5.8 and we wanted to go for a 5.3. We kno=
w
> from experience that a 5.3 ratio works well for the 1/2 SW level. We use=
d
> a capstan boat and found a position with an 8 degree angle that gave a 5.=
3
> ratio. We tested the dip with a 44.5mm/1.75" blow and it tested out at
> 11.0mm/.433". This certainly would not do so we checked the
> geometry. The capstans were set very deep in the key and the capstan/hee=
l
> contact point was way off the magic line. Everything else checked out
> except the height of the wippen and and hammer center pins. Apparently
> the action cleats were planed to thin in the Steinway factory. (Chris...=
.
> remember that Steinway D job we did were the tapered cleats had been put =
on
> backwards?)
>=20
> Tim shimmed up the brackets. The front by 5.0mm/.20" and the back by
> 8.0mm/.32", so that the center pin elevations matched the factory
> spec. (Yes we checked for clearance under the pinblock.) Then we set the
> capstan boat to make a 5.3 strike weight ratio and tested the dip with a
> short blow. Now it tested out to 10.2mm/.400" and we noted that the
> capstan/heel contact point came into acceptable alignment. Green Light!
>=20
> I hope this helps.
>=20
> David Stanwood
>=20
>=20
> _______________________________________________
> caut list info: https://www.moypiano.com/resources/#archives
---------------------- multipart/alternative attachment
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/caut.php/attachments/0e/06/6c/23/attachment.htm
---------------------- multipart/alternative attachment--
This PTG archive page provided courtesy of Moy Piano Service, LLC