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<DIV><FONT face=Arial size=2> Hey Rodger</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2> Are you currently using boxwood =
and do you
have or know of a source?</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Dale Erwin</FONT></DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV style="FONT: 10pt arial">----- Original Message -----
<DIV style="BACKGROUND: #e4e4e4; font-color: black"><B>From:</B> <A
href="mailto:baldyam@sk.sympatico.ca" =
title=baldyam@sk.sympatico.ca>jolly
roger</A> </DIV>
<DIV><B>To:</B> <A href="mailto:pianotech@ptg.org"
title=pianotech@ptg.org>pianotech@ptg.org</A> </DIV>
<DIV><B>Sent:</B> Saturday, April 21, 2001 2:52 PM</DIV>
<DIV><B>Subject:</B> Re: Fw: Bridge caps: box wood vs maple</DIV></DIV>
<DIV><BR></DIV>Hi
Ron,<BR>  =
;
Thank's for the added imformation.<BR><BR>This taken from a Schimmel =
hand
book.<BR><BR>Boxwood,<BR>SG Dependent on growing region, =
0.99-
1.02<BR>Growing regions, large areas of Europe, Asia, Japan and NW =
Himalan
regions.<BR><BR>Asia minor and the Caucasus is the main areas of =
supply.<BR>The
sapwood is pale yellow, distinguishable only by it's high moisture =
content, and
is very narrow.<BR>Depending on the growing region, the heartwood is =
dull to a
bright yellow. The pores are fine and widely seperated. <BR>The =
wood is
extremely hard.<BR>Regards Roger<BR><BR><BR><BR><BR>At 05:55 PM 4/21/01 =
+1000,
you wrote: <BR>
<BLOCKQUOTE cite type="cite">Roger, Dale and list,<BR><BR>The boxwood =
you are
referring to is<I> Buxus sempervirens</I>, which is a Roger says much =
harder
wood than Maple<I> Acer
=
saccharum</I>.<BR><BR>Species<X-TAB> </X-TAB><X-TAB> &nbs=
p; </X-TAB>Air
Dry Density
=
(ADD)<BR><BR>Maple<X-TAB> </X-TAB><X-TAB> &nb=
sp; </X-TAB>0.73
gr/cc<BR><BR>Boxwood<X-TAB> </X-TAB>0.9 gr/cc<BR><BR>I prefer to =
rate
timber density in grams per cubic centimeter, since water has a =
density of 1.0
grams/cc. This makes understanding the relative densities =
straightforward.
Wood substance has a basic density of 1.5 gr/cc. The wood substance in =
the
lightest hardwood Balsa ADD 0.2gr/cc to the heaviest hardwood Yarran =
ADD 1.3
gr/cc is the same at 1.5 gr/cc.<BR><BR>As Ron N and Roger mentioned, =
Boxwood
is now used for the top treble sections of Yamaha C series grands. =
Fazioli
uses Boxwood for the top section, then Hornbeam for the next, and then =
maple
for all of the lower string sections.<BR><BR>Steinway Hamburg used =
Boxwood for
the two upper treble sections until sometime in the 1980s. They now =
use maple
for all Hamburg Steinway bridge caps. Several earlier Hamburg pianos =
through
the 60s and 70s with Boxwood caps had problems. I noticed that the =
Boxwood
they used was often inappropriately cut on the cross, or even slab cut =
in some
cases.<BR><BR>Boxwood is so fine its difficult to determine the grain
direction by just physically looking at a bridge cap. But its pretty =
easy to
see when an old cap is sawn through.<BR><BR>I've often wondered why =
Boxwood
bridge caps are prone to failure, but there are two factors on my =
short list
of suspects.<BR><BR>Firstly, with a density of 0.9 gr/cc, these caps =
would
require a much larger drill than a maple cap to avoid excessive =
internal
pressure. We use a drill 94% of the pin size for new maple bridges. =
This
percentage would almost certainly split a boxwood =
cap.<BR><BR>Secondly, for
some years now I have suspected that the black slip coating which is =
applied
to most bridges may lead to bridge damage in commercial usage, when =
subjected
to high intensity lighting. The higher density Boxwood would be more =
prone to
thermal damage than the lighter rock maple.<BR><BR>Regards,<BR><BR>Ron =
O<BR><BR><BR><BR></BLOCKQUOTE><BR><BR></BODY></HTML>