[CAUT] CAF

[Jeff Tanner]

Hi Chris,
I sort of implied that in my second response, reply to Andrew.  You're absolutely right.

Fred,
Yes, practice at regulating spring tension does help. But my experience is that when balancier and hammershank pinning is too loose, the spring tension regulation has to be so light that it isn't reliable.  The spring has to regulated so weak that the slightest changes in humidity have a great effect on function. To regulate the spring tension so that it doesn't throw the hammer past the drop point against the string, creating the bobbling hammers at mp playing, you wind up with a spring not strong enough for the wippen to reset properly on a firm blow.  More firm pinning prevents "bounce", especially in the jack, but also in the hammer.  The stronger spring tension allowed by firmer pinning "lasts longer".

So, yes, I agree with Chris on this.  Yes, there are many causes, but every occurrence I've ever run into has to do with pinning, spring tension, or a combination of the two being out of tolerance on either side.  But I've always been able to remedy CAF with other means than changing the rest cushion height.

Jeff


  ----- Original Message ----- 
  From: Fred Sturm 
  To: caut at ptg.org 
  Sent: Friday, August 14, 2009 8:40 PM
  Subject: Re: [CAUT] CAF


  On Aug 14, 2009, at 5:02 PM, Chris Solliday wrote:


    Jeff T. is right when he says sluggish pinning of rep lever and jacks or weak springs are problems, well yes, that is obvious, but it's when the balancier is too loose that the real trouble begins. No matter how tightly you adjust that spring it can be pushed down by a heavy hammer returning on a heavy blow. Disaster. Pin balancier centers 4-9 grams (depending on how high your humidity gets in the summer) for best results.


  I know that a number of people have been advocating for tight pinning of balanciers, on grounds that it makes for better rep spring regulation and function. I am going to express a bit of skepticism about this. Granted, it will make it easier to do a bench regulation. Will it, in fact, make for better function? 
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