[Files] Steinway board design

[Erwinspiano@aol.com]

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   My Fellow belly heads
    In keeping with my own  current trend to improve the treble =20
function & overall crown stability in the Stwy design I thought it =20
might be of interest to some to have a birds eye view of the rib =20
layout without the soundboard panel in the way. With the bridge =20
located in place over it's respective position a birds eye view is =20
instructive.
   This design also  like the Recent S&S O design change incorporates =20=

one extra rib in the  treble. It is easily seen that the extra rib =20
allows for it's placement of the no. 9 rib to be placed directly =20
under the killer octave at C-6 and the no 11 rib moved higher up on =20
the panel for more support. I am finding these features to make for a =20=

really clear , powerful & sustaining tonal envelope & without the =20
usual voicing difficulties & limitations of the traditional design. =20
Frankly it's a relief. Rib fanning crosses the boards long grain at =20
more obtuse angles adding stiffness without mass( as I'm often told) =20
& also allows for taller narrower ribs.  The top 4 ribs are Sitka & =20
the rest white spruce.
    A variable radius crown is incorporated in the rib crowning. The =20
bass starting about 45 ft & ending at about  a 15 ft radii at =20
top.all  thickness of the panel is about .340 and thinned around the =20
tail and especially behind the bass for  bass response.
   There are many things not changes i.e. the scale or the bridge =20
location, bridge apron ,or many other features that are being =20
employed by my esteemed colleagues. I am not opposed to any of these =20
but  I have chosen to change what I consider the worst defects/=20
weaknesses in a given design first and proceed when I'm satisfied to =20
perhaps others. Also certain projects won't allow the budget to do =20
more elaborate  modifications.
   more below.......................

  =EF=BF=BC

   Below is the original board side by side with the new one. The rib =20=

foot print easily seen on each. The rib height on  Steinway designs =20
are dreadfully under supported which IMHO accounts for so many flat =20
boards early on. Also other factors include Spruce strength is =20
greatly stronger engineering material than the sugar pine which is =20
commonly used in C. C. assemblies.
   I've a S&S Long A in the works as well which is almost done .That' =20=

I'll post on as soon.as the results are known.  It has a sweeping cut-=20=

off bar & similar rib arrangements. It is my idea to be the test =20
guinea pig myself & try to fairly evaluate each design & chage as I =20
experience it. If any of you are in the area stop by & listen for =20
your self.
   Sincerely
   Dale Erwin
   Also & BTW
  I am absolutely not  denigrating any body else's design preferences =20=

be they Accurately made C. C. designs or any other by what I'm =20
posting as simply my own experience. I've made boards in a variety of =20=

configurations with about every spruce a rib stock available. Some =20
more successful than others.
   My experience right now is having  more reliable  outcomes every =20
time without the anomalies of the killer octave syndrome to deal with
    Dale Erwin

  =EF=BF=BC

Erwins Pianos Restorations
4721 Parker Rd.
Modesto, Ca 95357
209-577-8397
Rebuilt Steinway , Mason &Hamlin Sales
www.Erwinspiano.com



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