popsicle stick engineering

[Erwinspiano at aol.com]

Hey Clark
  What you describe I find myself  undoing  routinely on jobs that come in 
for a board.  The  statement is made that the action has been rebuilt but it 
doesn't play  well....it's heavy...fill in the blanks.  A well meaning person 
simply  made a decision without any action protocol information & chose the 
original  knuckle placement parts, Installed too heavy a hammer, which compounded 
original  poor key leverages etc.
  Whenever you find short dip & long blow the action  ration is high.  In 
this case probably 6.5 or more.  When initial tear  down is first contemplated, a 
quick regulation of one note will give you this  first clue as to action 
ratio problems. 5 minutes saves countless hours of  grief. AMHIK!
  A 17 mm knuckle often solves much of this leverage  problem or gets it 
headed in the right direction, but also a capstan move  is also needed to get the 
leverage into the ballpark. 
  I wonder if there is enough wood left in the keys to  salvage or if the 
rations are so whacked that a new key set is in order any  way.
 Stanwood made simple for me is as  follows.
  I have a action ration finder which is simply a  small 3 inch long by 1/2 
inch square block of maple that has a tapered 6 mm shoe  on the bottom & a 1/2 
ich lead in the top to hold down the key. With three  level white keys & three 
level hammers I can set this gauge on the keys  & in 5 seconds measure the 
amount of hammer travel in mm , then divide  by six & I have an action ration 
number that is close enough to tell me  which  way I need to go with the parts 
choice, capstan move & hammer  weight. A depth gauge placed at the top of the 
hammer which moved upward &  the bottom of the ruler in the gauge hit both 
hammer tops simultaneaously. ie  say 32 mm is a 5.33 action ration which is great. 
& 36mm would be 6 which is  going to have the problems you describe.
  Hope this helps
  I'll post a pic. later if you wish.......off to  
church.............................seeyalaterbye
  Dale

Hi, All!  I have been dealing with a S&S  B that I found with up to 9 leads 
in some of the low tenor keys.  All the  parts had been replaced with Renner to 
get rid of the Teflon flanges, but it  was heavy, sluggish, and just a chore 
to play for long.  I am not all  that familiar with the Stanwood protocols, 
but as time goes on, the concept  gets more and more attractive.  What I found, 
was that I had to shorten  the dip, lengthen the blow, to get it less 
laborious to play.  So, what I  suspect , is that the capstan placement is incorrect 
for the parts used, or  was incorrect from the start?  They also had the damper 
timing late to  try to make it feel lighter, so late that the hammer almost 
hit the strings  before it lifted.
    Ric, your comments on the more  creative combinations of blow, dip, etc 
hit a chord with me on this  beast.
    There were too many leads in  from the factory, and you could tell be 
looking that some more were added with  the new parts, as they did not look 
factory at all,  so the problems just  got worse, evidently with the parts 
replacement.
Clark A. Sprague,  RPT



 
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