<HTML> <HEAD> <TITLE>Re: [CAUT] Re: Moving Capstans</TITLE> </HEAD> <BODY> Hi Da= vid,   Good suggestion. Here they are. Alan        ORIGINAL NUMBERS         &nbs= p;            &n= bsp;   NOTE  A1    A#2     F9  =  F#10   C16   C#17   C28   C#29=   C40   C#41   C52   C#53  &nb= sp;C64   C#65   C76   C#77   B87 &nb= sp; C88   AVG    D       69     &nbs= p;67      65     70  &nbsp= ;   69      69    &nb= sp; 64      68      &= nbsp;65      63      57 &n= bsp;    60      58   =    57       71   &nbs= p;  79      63     67=    65.6    U       40     &nbs= p;37      34     36  &nbsp= ;   38      41     &n= bsp;43      38       41 &n= bsp;    41      36   =    35      39      37=       48      47  &n= bsp;   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  &n= bsp;12.5     9.5    10.0   &nbs= p;11.5   16.0    9.5   10.5   1= 2.8    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  &n= bsp; 48.5   47.0    59.5   63.0 &nbs= p; 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  &n= bsp; 15.6   18.1     1.9   &nbs= p; 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 &nbs= p;   8.6      8.2    =  8.0      7.2     7.3 &nbs= p;   5.4    5.5      R       7.1     7.2=     7.1    7.2     7= .1    7.2      6.8   &nbsp= ; 7.1    6.9     7.1   &nb= sp; 6.8     7.2      6.6 &= nbsp;   6.9      7.1   &nb= sp; 7.4     7.1    6.9   &= nbsp; 7.0      NOTE      KR      &= nbsp;WW        WBW    16         0.56   &= nbsp;18.1        10.14    17         0.56   &= nbsp;18.0        10.08    40         0.57   &= nbsp;18.2        10.37    41         0.56   &= nbsp;18.2        10.19    64         0.56   &= nbsp;18.5        10.36    65         0.56   &= nbsp;17.7          9.91  <= BR>  AVERAGE WBW =          &= nbsp; 10.18               KnuckleCore/CnterPin = 16.0    Capstan Convergence? No , Too low  Bass Action Spread: 4.438”    Treble Action Spread: 4.438” > From: "David C. Stanwood" <stanwood= @tiac.net> > Reply-To: "College and University Technicians <caut@ptg.org&gt= ;" <caut@ptg.org> > Date: Tue, 26 Oct 2004 11:03:05 -0400 > To: <caut@ptg.org> > Subject: [CAUT] Re: Moving Capstans > > Alan, > > I can't access your .xls file either... > How about just giving us typed columns of numbers such as: > > N   U   D    FW    S= W    KR    WW > > 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 > > The above minimal sample notes give a good idea of what's going across= the > keyboard. > > To answer your question:  You can tell how far to move a capstan = by looking > 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 yo= u have a > ratio which is 6.0 and you want to achieve a 5.5 just plug in the numb= ers > and solve the equation for BW: > > BW=(SWxR+WWxKR)-FW > > The result is your new target BW for making your desired strike weight= ratio. > > 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. > > When working with an existing heel cushion and a 90 degree capstan I d= o not > recommend just moving the line but rather angling the capstan backward= s and > bringing the capstan line forward so that the capstan contact point on= the > heel shifts forwards.   For a small, medium, and large effec= t, try 4, 8, or > 12 degrees.  <a href="http://www.stanwoodpiano.com/CapRoll2.jpg">= http://www.stanwoodpiano.com/CapRoll2.jpg</a> > > 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 we= ight, my > formulas offer the clearest solutions. > > As for Geometry... follow the rules and make sure you can regulate it.=  If > you are going for lower weight ratio (5.0 - 5.8) expect to use a minim= al > blow distance of 44.5mm/1.75".  If you move a capstan line, = test the result > before committing to the new line.  If the dip is too deep for a = short blow > distance then don't do it! > > 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 = work > on.  The strike weights were in the TopMedium range and he had te= sted 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...<BR= > > > The average SW Ratio level was 5.8 and we wanted to go for a 5.3. &nbs= p;We know > from experience that a 5.3 ratio works well for the 1/2 SW level. &nbs= p;We used > 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 te= sted out at > 11.0mm/.433".   This certainly would not do so we check= ed the > geometry.  The capstans were set very deep in the key and the cap= stan/heel > contact point was way off the magic line.  Everything else checke= d out > except the height of the wippen and and hammer center pins.  &nbs= p;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 p= ut on > backwards?) > > Tim shimmed up the brackets.  The front by 5.0mm/.20" and th= e 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.  &nbsp= ;Green Light! > > I hope this helps. > > David Stanwood > > > _______________________________________________ > caut list info: <a href="https://www.moypiano.com/resources/#archives">htt= p://www.ptg.org/mailman/listinfo/caut</a> </BODY> </HTML>