How much tuning pin in pinblock?

[Farrell]

How much tuning pin in pinblock?You are absolutely correct Paul. I think maybe I forgot to put my thinking cap on. But yes, you are correct that I will leave the pin a bit up from the bottom of the hole. I tend to put my coils pretty close to the plate - closer than many do - so I guess I don't have much free space at the bottom of the block.

Terry Farrell
  ----- Original Message ----- 
  This may be based on a dismaying misapprehension of the reality of the world (much of my life is, after all), but I have always thought that there has to be room for the pin to be driven further into the block as necessary as the block ages and pin torque drops. If there is no dimension available at the bottom of the tuning pin hole for this, the pin is then driven below the level of the block with all its awful consequences. So I have always just used the dimension available between the coil and plate as the guide as to how much room I want at the bottom of the pin hole. If I were to drive the pin down gradually, I would want to know that, when the coil is approaching the plate (never less than a string's diameter), the pin is still in the block and not extending below it.  Surely, you don't drive the pin entirely to the bottom of the hole when you're stringing? I agree absolutely entirely with your sentiment below about more is better. But this is one of the small compromises I make to create a practical life to the pin/pinblock structure. Does this make sense to you?

  Paul 


  "If you want to know the truth, stop having opinions" (Chinese fortune cookie)


  In a message dated 03/25/07 07:19:16 Central Daylight Time, mfarrel2 at tampabay.rr.com writes:
    I don't claim to have any real expertise to answer this question - more opinion and more questions.

    It seems to me that one would always be better off with more pin in more pinblock - how/why would it be any other way? The more length of pin in the block will only make the pin more stable - less likely to enlarge the top of the hole toward the string. The more pin/block contact, the less friction per contact unit would be needed for any given pin torque - meaning more stability and longevity. Just seems to me that more/more could only be win/win.

    Paul - what is your reasoning for leaving any empty tuning pin hole on the underside of the pinblock - and then especially, what is your reasoning for relating that distance to coil height? How is one dependant/affecting the other?

    Terry Farrell
      ----- Original Message ----- 
      Correct me if I'm wrong, but I've always aimed for a tuning pin/block relationship that, irrespective of the actual measures, ends up with the same dimension between the coil/plate as there is at the bottom of the pinhole in the block. In other words, if the coil height is, for example, 3/16", then there should be approximately 3/16" available between the bottom of the pin and the bottom of the pin hole/bottom of the pin block. The other dimensions then sort themselves out if one chooses the right pin size and block thickness. Does that make sense? It almost always works out to approximately what you calculated: between 1" and 1 1/8" of pin in the hole. 

      Paul
        >How much of pin should ideally be in block?


        As my grandmother used to say to my relatives when divulging ingredients
        for recipes for her fantastic pies: Enough but not too much.


        Generally speaking, The top of the pin usually is anywhere from 7/8" to 1"
        above the plate. Allowing for a 3/8" thickness of plate at tuning pin field,
        with a 2 3/8" pin, that leaves 1" and 1 1/8" into the block respectively.


        Subtract from that the 3/16" bevel at the bottom of the pin, leaving...
        um... er... why can't we use metric?  :-) ...   Enough but not too much...


        A lot depends on the block material and bore diameter/drill speed.

        Jon Page

-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20070326/f3f87d65/attachment.html