NY Steinway Ribs and MC

[Farrell]

----- Original Message -----
> Just got back from NY where I got the opportunity to do a long 
> personalized tour of the factory.  As always one sees too much in too 
> short a time to take it all in, but I had my eyes open for a couple 
> special particulars.  When passing the rooms for soundboard and rib 
> dry-down just prior to glue up I noted posted beside the doors the target 
> MC for both.  So here is the absolute straight skinny.
>
> Soundboards are dried to 3.8 to 4.5 % depending on the season. Ribs to 8.6 
> %.  Both are put in their respective hotboxes for 3 days prior to glue up. 
> The ribs are flat as we have been made to understand, and they glue them 
> in shaped dish cauls (I saw glue up in the restoration room only f.o.s.) 
> pressing the SB into shape and then ribs into resultant curves.  Bridges 
> are cut to match the resultant curvature along its footprint by a 
> computerized cutting machine.

A computer! Good golly! Not hand carved by some grey-haird fifth generation 
piano craftsman?

Ahhhhhhhhhhh - the sky is falling, the sky is falling.......!!!!!!!

> This was very different from the Hamburg process. Hamburg did not use 
> dished cauls do begin with, but individual cauls for each rib length.  Nor 
> did they have a dry down room for either prior to glue up.
>
> I'm unsure of to what degree using dished cauls will affect the after glue 
> up shape. Straining the panel in directions other then perpendicular to 
> the grain before glue up ?? Have to think about that one :)

I can't imagine it would make any difference - whatever bending occurrs 
along the grain will just pop right out when removed from the dished caul 
(assuming the ribs are nearly perpendicular to grain).

> Anyways... this stands in contrast to the post I have referred to 
> previously from John Patton

And what does Patton have to say - how does what you observed differ from 
what you understood from John Patton?

Terry Farrell

> I am unsure of why. It may be that they have some short waiting period 
> between removing the panel and ribs from their respective hotboxes before 
> actually gluing them together.  The rooms are quite warm and wood inside 
> as well. Perhaps they need at least to let everything cool just a bit ? 
> The person guiding me was unsure of that answer and we didn't get the 
> chance to confirm one way or the other.
>
> Cheers
> RicB
>
>
>