Re-pinning question

[James Ellis]

Gentlemen:

I am at that stage in my life where I send all my pinblock, repinning,
restringing, etc. out to a local shop that does excellent work.  He
frequencly calls me in to check out an action he has rebuilt.  Having said
that:

The question is whether to go up one size of two sizes when repinning:
That depends upon a lot of things.  If it's a high-quality five or six-ply
maple block, going up two sizes is probably OK, especially if the block is
still resilient.  If it's one of those very-high-density multilaminate
blocks, and you go up two sizes, you will be in trouble, especially if the
new pins vary is size and you don't mic and grade them first.  

You also get into trouble at the bottom end of the pin where there is a
shoulder left over from the compression left by the old pin.  That's where
the de-lamination is going to start, despite the fact that you support the
block when driving.

I am of the opinion that one should ream the hole first.  NOT to make it
bigger, but simply to remove that shoulder and make the hole round again.
The problem is, I have not found one reamer that's right for the job.  The
ones that are out there that I have found just make bad matters worse
because they are made wrong in the first place.  If I live long enough, I'm
going to design one that works.

When you do support the block, don't just put a support between the block
and the keybed.  Also support the keybed with something like a 4x4 or a
jack post right down to the floor.  You will be surprised at how much
better everything works when you do that, especially if you are on a solid
concrete floor.  The pins will drive easier and with less noise, and you
won't traumatize the keybed so much.  Also, make sure your support is
massive and fits snug against the underside of the block.  This applies to
new pinblocks as well as old.

And one last thing that's already been discussed:  Tuning pins vary in
sise, and some are out of round.  Some are slightly bent.  And one thing I
have sometimes seen that's not been addressed here is "drunken" threads.
Drunken threads are where they wobble, and don't form a true helix.  That
sort of thing is going to chew up the block, be it old or new.

Most of you already know what I have just said, but there may be a few of
you who will find this to be helpful.

Sincerely, Jim Ellis, RPT  

At 05:58 AM 3/12/03 -0500, Phil Bondi wrote:
>..question regarding re-pinning a block..
>
>I've always been under the understanding that if you are going to just
>re-pin and re-string, you go up 2 sizes on the pins, correct?
>
>Not always?
>
>I have a piano in my possession that I believe could go up just one size,
>from 2's to 3's, because the torque is solid across the block(70-100lbs.).
>I'm afraid if I go up 2 sizes, I'll need a 12' breaker bar to tune with.
>
>Replacing the block is not an option. This is a dealer's used piano, and he
>wants minimum work for maximum return. I can't argue with his assessment of
>the block..it's a Baldwin E for those of you still reading..
>
>Suggestions? Comments? Concerns?
>
>-Phil Bondi (Fl.)
>phil@philbondi.com
>
>
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