[pianotech] composite pinblock- Drill bit size

[Dale Erwin]

  Hi Dave
  With the dissimilar fits of both those materials being in my opinion huge you may be unhappy.  Ron's advise to glue some up and try it is the best advise.  
  I also build my own blocks similar to Bolduc/Steinway and cap it with only 6 mm of delignit pin block material. 
    The threaded portion of a  2 & 3/8ths pin protrudes into the block only 1 inch so you delignit is over 1/3 of the pins penetration into any block...&  in your case. and the portion closest to the tuning pin force.  I have checked this many times.
   Drilling  according to the delignit bit recommendation you may as well attribute little grip from the Bolduc portion. With the Multi lam many use the drill size can also be drilled larger and will be more compatible with the delignit top cap requirements . The Quarter sawn Erwins & Farrell type Blocks require a .257 or .255(metric) for a correct beautiful pin fit. Delignit is .272.  A huge variance...Aye?
  Is the material you are using for top cap the Bridge cap stock? If so it is more compatible with quarter sawn blocks.  There is a difference and IMO between the bridge cap delignit and the pinblock stock.  The bridge cap stock has more layers and seems to be oddly less dense than the pinblock stuff.  I like it.
  Here in lies the problem child.  If you are choosing the to cap with such a thick layer of delignit pinblock stock then I don't see the point of wasting a $400.00 bolduc block. May as well use delignit anyway.  Its not a bad feel when drilled right. If you choose to use delignit bridge cap stock then put a thinner layer on top and have a great feel,flagpole control and less maple waste. A fantastic feel.  I got my first one from Farrel.
  See what I mean

 

Dale S. Erwin
www.Erwinspiano.com
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209-577-8397
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-----Original Message-----
From: David Renaud <drjazzca at yahoo.ca>
To: Pianotech <pianotech at ptg.org>
Sent: Thu, Sep 23, 2010 5:33 am
Subject: [pianotech] composite pinblock- Drill bit size


  For a Boesendorfer grand I have laminated 3/8 delignight for the 
open faced top sections onto 1.5 inch bolduc block. Fit seperately
and glued togther.
  The suggested bit for Bolduc's block is smaller then the suggested 
bit for delignite as Maple has so much more give.

   Can those that use, or make composite blocks share their 
experience. I'm considering drilling with the Bolduc
bit and following up with redrilling for the delignite 3/8th deep only.
........???

                                 Thank You
                                 Dave Renaud 
  





 
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