Fwd: Make a soundboard--Measurements

[Erwinspiano@aol.com]

---------------------- multipart/mixed attachment

-------------------------------1067124531
In a message dated 10/25/2003 8:06:48 AM Pacific Daylight Time, Erwinspiano 
writes:
PM Pacific Daylight Time, davidlovepianos@earthlink.net writes:
   Dave
   Good post, good ideas. To me this part a very important aspect of "Making 
a sound board" & making it work.  I figured that this thread would cover many 
aspects of good belly work and without good bridge work & bearing setups the 
board won't work at its optimum. I'm hoping other rebuilders will offer 
alternate techniques on any phase of this procedure. I've already learned something 
new to try.
 I my self will try this technique although I don't have much problem with 
the mylar way, especially the 10 mil stuff but it's important to be on the 
lookout for unparallel front and rear pin lines & to refrain from copying mistakes. 
Any technique that builds accuracy I'm all for it.
   When I started the tear down list yesterday I forgot to include scribing a 
line on the belly rail where the guide rails are attached and the treble caps 
screws are located. I like to hit the original hole whenever possible & 
appropriate, which is usually. Also I record the angle of the boards grain 
orientation off the spine/flat side. Most older boards are either 40 or 45 degrees.
   Knocking out the board is kinda of fun actually. It's also an acquired 
technique. So since all the relevant data has been recorded. We usually stand the 
piano on its side and Trix , the boys & I take a piece of heavy pin block and 
start hitting the rib end at the case to break the glue joints loose. A 
little pop usually tells you there letting go. I try to get it out intact as 
possible but it's going to splinter up some. That's OK. We just tape the pieces back 
on later for a clearer picture of the board. I save the rib ends where 
feathering is so I can copy these to whatever degree I wish. I use a crow bar or 
whatever I can get in along under the belly rail to pry it out. Some boards 
practically fall out, others just don't want to leave home.
     
   Regard-- Off to the College to catch up--Dale
The bridge I just did I ended up laying out from scratch rather than trying 
to follow a pattern, an idea I got from Del Fandrich.   I found this to be 
easier and more accurate since I was rescaling and making slight alterations to 
the speaking lengths.  It also allows you to avoid duplicating mistakes on the 
previous layout.  The method I used was to first mark on the plate the center 
string locations on each hitch pin.  I used a dummy tuning pin with a string 
attached (Mazzaglia) which I put into the center tuning pin hole on the plate 
and wrapped the string around the corresponding hitch pin.   Eyeball the string 
in a straight line through the capo (or from the agraffe) and over the bridge 
and make a pencil mark right under the string on the front and back of the 
bridge.  Take a small straightedge and draw a line, move to the next one.  When 
you are done look at the overall spacing and make any co! rrections to get it 
looking even.  From there measure your speaking lengths and mark on the line 
the front center pin location.  Using one of several three hole punches I also 
got from Mazzaglia (depending on spacing), mark you pin locations.  Measure 
from the front row to the back row at whatever pin spacing you are using and mark 
the back row center pin.  Using the three hole punch, mark the back row.  At 
that point, if you are going to paint graphite on the bridge to, do it then, 
it makes it much easier to see where you are notching if your eyes aren't as 
sharp as they once were, like mine.  Drill your bridge pin holes.  Then mark the 
side of the notch at 90+ degrees (whatever you use, I use 93) off the front 
pin line.  I use a small piece of mylar cut at the proper angles which a lay 
along the pin line.  Look over your markings to see that they are evenly spaced. 
 Cut along the line with a small saw to unif! orm depth (don't overshoot the 
hole, use a chisel for that last bit).  Then cut your notches.  

I've gone beyond my point a bit, but I found that laying out the bridge from 
scratch eliminated worrying about how precise the pattern was and trying to 
copy it.  I still make the pattern because it gives me the location for screws 
in the top of the bridge when I am gluing down the new cap (on an old board), 
and lets me know generally where I should cut my bearing points, and out of 
habit.  But laying out new gave me better results and it may even have been 
faster.  

David Love
davidlovepianos@earthlink.net

-------------------------------1067124531
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/63/36/9b/1b/attachment.htm

-------------------------------1067124531--

---------------------- multipart/mixed attachment
An embedded message was scrubbed...
From: Erwinspiano@aol.com
Subject: Re: Make a soundboard--Measurements
Date: Sat, 25 Oct 2003 11:06:48 EDT
Size: 11435
Url: https://www.moypiano.com/ptg/pianotech.php/attachments/f8/90/78/f8/attachment.eml

---------------------- multipart/mixed attachment--