action ratios

[Erwinspiano@aol.com]

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.> 
> 
> Dale Erwin Wrote:
> 
> >micro-balanced action I'm finding it a whole lot more effective and
> efficient, all be it more expensive, to design the action and key ratios
> together by having a new key set made. Roseland makes affordable key sets
> and sooo many or the old actions frankly have been recovered, resoled ,
> rebushed, and yes even repainted to the point of necessary replacement that
> it only makes sense to go in this direction. Oh also I left out; just awful
> original geometry that moving the capstan, etc., will not fix.
> 
> Dale,
> 
> "Regarding awful original geometry".  Care to be a little more specific?  A
> new keyboard won't fix a problem with stack geometry.  If you mean a ratio
> problem can be fixed with a new balance rail position, I don't find that it
> makes a difference in the overall regulation or ratio by moving the
> capstan/heel line vs. moving the balance rail so long as the rule for the
> line of centers is observed.  I've moved capstan/heel line as much as 1/2"
> to make a 5.5 ratio and that action regulates 10mm/44.5mm.  It certainly is
> nice to have a brand new keyboard for sure... just make sure your putting
> those key leads in the right place for posterity!
> 
> David Stanwood
>         
     Hi David
          What I was referring to was mating the stack geometry with a new 
key leverages that work for weight and regulation needs. If the keys are a 
disaster, the better repair is starting over. Also if you've calculated for 
heavier desired hammer/strike weights for you system ahead of time these 
factors can be taken into account in setting up a new system but you know 
this. I'm guessing you've encountered the (particularly Stwy) capstan line 
that tapers so much bass to treble that the regulation changes gradually from 
one end to another (either the blow changes to accommodate the dip or vice 
verse). If the keys are already toast why move the capstans. Get new keys. 
This is my rationale. 
    Also Capstans that can't be moved enough to get good lines of convergence 
even with as much change in stack geometry improvement as possible. A recent 
Baldwin C from the 20's comes to mind. I moved the capstans 10 mm forward to 
the very front of the wippen heel to get a better convergence line. It would 
have benefited greatly from having a new balance rail position  moved even 
closer to the capstan In this case the client didn't want to spring for new 
keys. Also the other restriction was that of all the wippens available from 
any supplier there was only one that fit and it was from Renner.
    In the case of the Baldwin hypothetically if I would have had new keys 
made it's that the capstan position could have remained in the same location 
and repaired the convergence line this way.  In that scenario with balance 
rail position being moved 10 to 12 mm towards the capstan (which is huge)  
creates a longer leverage capable of lifting the weight of the action parts 
more efficiently and with less lead or am I missing something here.
  A Case in point, if you take stwy player grands with that extra long key (3 
inches)? with low amounts of lead it would be possible to carry any amount of 
hammer weight you wished. It's a better lever or has the potential to be with 
appropriate stack geometry.
  Hey the real problem is that keys in general are just to danged short. But 
really on smaller pianos they are and that's why more action balancing 
gymnastics are required
     I'm guessing your point is that you've moved a lot of capstan without 
replacing keys and solved many gross ratios problems and still maintained 
acceptable regulation specs. 
          Dale Erwin
      

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