Drill bit size for #1 gauge tuning pins

Erwinspiano@aol.com Erwinspiano@aol.com
Wed, 6 Oct 2004 11:04:38 EDT


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Ron
   By the way
  Your thoughts & method on the capping rotary blocks  makes a whole lot a 
farm boy sense. I'm gonna try it. A 2 3/8' pin is only going  to end up with 
half its length in actual wood (well depending flange  thickness)  Which means 
the portion  in the wood has about equal  parts in botht he 15/32" & then 
delignit cap & rotary cut maple.. ahh  very slick I get it.  what drill diameter 
does this set up like to bore  at?
  I'll send the leftover cash right away
   Thanks
  Dale

That's  no different from the quarter sawn blocks. They self destruct under  
extreme conditions too. The only disasters I've seen from the cheap blocks  
(assuming competent installation in the first place) were in school  systems 
with steam heat where the RH% went from over 75% in the summer, to  under 
20% in the winter. In fact, that's one of the reasons I originally  went to 
Delignit many years ago. The multi-lams tended to be snappy if  they were 
drilled tight enough to hold up under climatic abuse. The  Delignit will do 
that too, but the double drilling helps that, which is  one of the reasons I 
developed the process. The problem (among other  things) is that the bottom 
of the hole is as tight as the top of the hole,  and it doesn't need to be. 
There's almost no string induced stress on the  pin and block at the bottom 
of the pin, so the bottom half of the block  serves mostly to keep the pin 
pointed in the right direction, and supply  the snap of jumpy pins when it 
gets the chance. A low density block capped  with the Delignit bridge 
capping stock changes the torque gradient down  the pin, and lets the bottom 
catch up with the top without kicking the top  loose and snapping. Again, 
this works with both the $75, and the $315 low  density block. It is my 
expectation that, since the majority of the  tension and leverage is 
supported by the much tougher capping, the  underlying block is under 
considerably less load than if it were doing all  the work itself, and won't 
deteriorate nearly as badly or as quickly under  climate extremes as a 
result. Lower compression levels ought to mean less  compression set. That's 
the theory, anyway, and that makes the expensive  block a waste of money and 
good wood. I like it so far, but I'll let you  know in 20 years or so how it 
works out in long term practice.

Ron  N


 

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