At 10:04 AM -0500 4/13/03, Ron Nossaman wrote:
>>Was that a solid bridge root with a ship-lap joint, or vertically laminated?
>>
>Solid, why?
I just wasn't used to hearing that a long bridge of maple was that
floppy, and thought that the difference in stiffness between
vertically laminated and solid might account for your testimony.
Back when I thought I was going to be going deeper into belly work
than just repair of old boards, I made myself a vertically laminated
long bridge, gluing strips of rotary sawn 1/8" maple veneer (locally
available) next to the long bridge I'd pulled off a dead upright. I
ran both sides across the jointer and practised notching.
Last night (25 years later) I pulled it back out of some dark corner,
and laid it on my granite panel: just as flat as ever. It's been
sitting for a day now, balanced at mid-point on a pencil and is still
flat. I can push it flat without too much trouble, but it springs
back flat quite emphatically.
>These are new pianos I've tuned for dealers, either on the dealer's
>floor, at sales events, or in customers' homes. These are not
>necessarily pianos with any specific complaint I was called to
>alleviate, though some were. I don't see that it matters a whole lot
>if the soundboard dies in the factory, in the truck on the way to
>the dealer, or in the customer's home between the time of delivery
>and the tuning. This shouldn't be happening at all, in my opinion.
>
>>How many were these?
>
>Dozens, not hundreds.
I'll take your word for it. My condolences to the owners (if they've notice).
>>And how many new Steinway pianos have you been called in to examine
>>because of perfectly fine tone, in which you found the required
>>crown.
>>
>Now that you mention it, I don't recall ever being called in to
>examine a piano because of perfectly fine tone. How many times has
>this happened to you?
On the surface this was a joke. (Like the comment from a
Medecin-Sans-Frontier doctor on the other side of the Paki border
from the Afghan civil war fifteen years ago, that none of the land
mine victims making it to his clinic had leg wounds.) The rest of the
paragraph did confirm that you've run into good Steinways as well.
>No Bill, it's somewhat more than less than one. How is it that you
>apparently aren't experiencing these problems? Do all (both?) of the
>Steinways you service sound perfect? How many pianos have you
>checked crown and bearing on, and what correlations have you made
>between these measurements and tone production?
Truth be told, I don't see that many new Steinways. Saxtons River VT
is a nice town, but it really is out in the pucker-brush, as far as a
constant supply of people ready to purchase a new Steinway. Now that
you mention it, whenever I've sold a big ticket Steinway, it's
generally been from a rebuilder. The Steinways at the dealer just up
the river from me aren't very compelling to me or my customers. I've
always assumed that whatever could be made of these pianos would be
"after-market voicing", but I certainly would have learned a great
deal, as you did, checking bearing at various points on these boards.
When I want to see good fresh Steinways, I grab a Sunday in July and
go down to the Marlboro Music Festival. The best most recent Steinway
I've encountered was a Dakota Jackson Design AIII belonging to a
customer. Laying a string on the underside of that board might reveal
what was right where all these others were wrong. It's a very strong
piano (not in the Jesse Ventura sense, but in the aspect of sheer
size of tone which a voicer has to work with.)
>Were all those hours of discussion about the drawbacks of
>compression crowning soundboards for nothing? It's essentially a
>design problem. This sort of thing is inherent in the production of
>compression crowned soundboards.
Don't mind me. I've just had to run another sacred cow through the
meat grinder. I going to have to turn the bulk of it into patties and
go through it, burger by burger, over the month six months.
Regardless of Terry's bald dome sticking through his topless hat, the
only curvature which the ribs provide is perpendicular to the board
and bridges. Any curvature in the board parallel to the grain and
bridges would seem only to come from a special shaping of the belly
rail and the rasten. That shaping that would seem to be an even
trickier piece of wood-working (its pattern having come from the
intersection of a paper "doughnut, whose hole was shaped more like a
piano rim than a circle).
It would seem to me that the ribs, and the crown they provided, would
be all the support for the string load the board would need. Any
crown parallel to the board grain and bridges, with the panel out of
the rim, would seem to be spurious and inconsequential, all the more
so because at the end of the day, crown in that direction has nothing
to do with any belly work, but simply the shape of the rim.
But all that having been dispatched, there is a small residual matter
which John Hartman may have been referring to. I've never done any
bellying, but I'd guess that there is nothing about the ribs, once
glued on which would get in the way of bending that spruce panel up
or down, parallel to its grain. (Yes, I know about how much stiffer
any wood is long the grain than across it, and also that the contact
area of the ribs and their glue lines will provide an extra stiffness
which an engineer could measure.)
At this point we do have the matter of two springy pieces of wood,
the large (piano-rim shaped) pancake of spruce, and the long stick of
maple. If they aren't mated, then in the gluing process, the one with
the greater spring strength will overcome and deform the other (or
more likely be the less deformed of the two in the laminating). But
then the two of them together will have this resultant shape,
overcome and deformed yet again as clamps and glue fasten them to the
far stiffer rasten.
(Jeeze, i forgot and left the meat grinder on all that time.)
So apparently it doesn't matter that when a poorly mated bridge
bottom and soundboard top are glued together, the resultant joint
will have an inherent stress. (The stronger of the two springs will
bend the other.) But this is nothing which crowned ribs aren't doing
to the board perpendicular to the grain. And it if did matter,
correcting it would require that extra step of fitting not just the
bridge to the board, but the rasten to the resultant board curvature
around its perimeter. In both cases, not just extra hours, but stock
removal which cut put the rest of the belly process at risk.
Let me know if i have to write something on the board 100 times, but
don't ask me to eat more that ten burgers a day. <g>
Bill Ballard RPT
NH Chapter, P.T.G.
"Never try to teach a pig to sing.
It wastes time and annoys the pig."
...........Sign on the wall of a college voice teacher's studio.
+++++++++++++++++++++
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