Bolduc Block - Bit Size - Torque

[Greg Newell]

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Terry,
         It's been my experience that a block will relax a bit after the=20
initial results from stringing. You may start out with 200 or so and end up=
=20
with 170-175. Didn't you save a piece of the pin block you used and run=20
some tests with different sized bits and pins?

Greg



At 08:15 AM 6/17/2003, you wrote:

>I am stringing a piano that I installed a new Bolduc quarter-sawn=20
>(more-or-less) hard-maple pinblock. I am using Ron Nossaman's two-bit=20
>drilling method. I started out with a final drill size of 0.25-inch=20
>(actually the drill bit that Pianotek sells specifically for the Bolduc=20
>blocks - it is actually about 0.247-inch). I was consistently getting an=20
>initial torque exceeding 200 in.-lbs. I tried a couple larger bits that=20
>produced similar results. I have drilled my latest holes with a final bit=
=20
>size of 0.263. I am getting an initial torque (right after pounding the=20
>pin to stringing height) of about 180 in.-lbs.
>
>At 180 in.-lbs. I feel like I am at the upper limit of what I should be=20
>shooting for (beyond?). How much can I expect the torque to fall in the=20
>first month/year or so when things settle in? My guess is that I could go=
=20
>with an initial lower torque, but I am concerned that perhaps things are=20
>going to loosen up and I might be too loose if I use a larger bit (I'm=20
>already so much bigger that what is commonly recommended).
>
>The block has been in my 8.5% MC-stable shop for more than six months.
>
>This is only my third block that I am drilling. If I am going to error, I=
=20
>would rather error toward the upper limit. Both my others were about 200=20
>in.-lbs. - YIKES! This is my piano - I don't want to have to tune with=20
>such a block - yet, loose pins do no one any good.
>
>Thanks for any constructive input.
>
>Terry Farrell
>_______________________________________________
>pianotech list info: https://www.moypiano.com/resources/#archives

Greg Newell
Greg's piano Fort=E9
mailto:gnewell@ameritech.net=20

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