This is a multi-part message in MIME format.
---------------------- multipart/alternative attachment
Get two blocks of wood measuring exactly 7" high. Place them on the =
soundboard at opposite edges of whatever part of the piano you want to =
measure. Put a straight edge across the top of the two blocks and at a =
point midway between the blocks, measure the distance from the bottom of =
the straightedge to the soundboard. Subtract that number from 7" and =
the amount left over is the amount of crown.
David Love
----- Original Message -----=20
From: St=E9phane Collin=20
To: Pianotech=20
Sent: December 18, 2002 4:41 PM
Subject: Re: Bridgetop Extravaganza Revisited
Hello Stephen
Am I alowed to ask a kind of stupid question ?
How do you measure the crown on the top of the board ?
(I am interested)
St=E9phane Collin.
----- Original Message -----=20
From: Stephen Bellieu=20
To: Pianotech=20
Sent: Thursday, December 19, 2002 1:00 AM
Subject: Re: Bridgetop Extravaganza Revisited
Greg,
It's definitely quartersawn. I don't think it's a candidate for =
recapping for two reasons. The board is dead flat across the bass =
bridge and lower tenor bridge (as measured from the top and confirmed on =
the bottom). Also I have learned the piano was purchased by the client =
new some 16 yrs ago. I have no intention of condemning this piano. It =
sounded ok before. Not spectacular bass but I have heard much worse. =
I'm anticipating tight new bridge pins are going to contribute to tonal =
improvement up higher.
I'm wondering about the bearing in the bottom of the piano. How =
it was originally set. Strung it showed a full 1.5 deg across the bass =
bridge and almost nothing on the bottom two feet of the tenor =
bridge.(also no front bearing in both of these locations) Is this what =
flattened out the tail ? If I relieve some of the bearing across the =
bass bridge will this improve the situation? I'm used to seeing older =
pianos with little bearing on the bass bridge. Opinions?
Steve Bellieu
P.S. Thanks for all the welcomes. I know some of you and recognize =
lots of other names from Journal articles and tips.
----- Original Message -----=20
From: Greg Newell=20
To: Pianotech=20
Sent: Wednesday, December 18, 2002 12:32 PM
Subject: Re: Bridgetop Extravaganza Revisited
Steve,
Now that you've decided to pull the plate I would strongly =
recommend simply recapping the bridge with quarter sawn material unlike =
the flat sawn junk you'll be removing. I' ve never seen quarter sawn =
material dented as badly as you describe, even by well meaning newbies =
with a hammer and screwdriver. A couple runners on the router and skin =
off the old cap. Put on a quarter sawn cap of good solid material. Re - =
drill, notch and restring. I'll lay odds you'll be greatly pleased with =
the result!!!
Greg Newell
P.S. Welcome to the list!!!
At 05:13 AM 12/18/2002, you wrote:
Hi All, =20
Just joined, first post to this or any other group. =
Serendipitous timing, just read all the recent bridgetop/ bridgepin =
posts. Have a 1985 Stwy D in the shop for action overhaul and restring. =
I thought I was noticeing something funny about the bridges but was in =
denial until I started taking all the teardown notes. The plain wire =
strings have been pounded (seated) into the bridge so that at the edges =
there is more wire diameter below the bridge top than above it. When =
viewed from the side the wire makes a pronounced curve up onto the =
bridge and down again out the rear making accurate component readings =
impossible to do from on top of the wire. It was showing negative front =
bearing until I realized what was happening and started using the actual =
bridgetop as reference. Situation is most severe at capo sections and =
diminishes down to what looks like normal grooves to me under the bass =
strings. Deflection in strung piano is .5 deg at bottom of low capo, =
1-1.5 deg rest of capo sweeping up to 2.5 deg at note 88. There is =
.250" crown at low capo. (measured from top of board) =20
Is it possible this condition is due to the quality of the =
capping material? I usually work on much older instruments. I have =
never seen string cuts like this. Also the various pressures have =
caused dead wood to swell up and check here and there around the =
terminations. Again I'm not used to seeing this. Inspection of the =
pins under magnification shows the string resided in two distinct =
locations. My theory: Pre- and Post Pounding. There are also a lot =
of unexplainable nicks on the side of the pins. The pins pull out =
easily. No cracks to speak of. This is an institutional piano which =
has probably been in Southern California its whole life.
What I'm thinking about doing is similar to what Dale Erwin =
just posted. I've never done the epoxy bridge thing but I'm familiar =
with the nasty stuff. I'm imagining thickening it enough with colloidal =
silica so it won't run down the notches or too much into the holes and =
applying it with a small spatula. I want to fill those deep grooves (at =
least on the speaking side) and then sand the top flat. If I put the =
stuff on in the morning can I pare/renotch and redrill at the end of the =
day before it gets too hard and while I can still find the original =
holes?=20
Looking forward to peoples responses.
=20
I want to stop using the misnomer "string seating" in favor =
of wire straightening (or something similar) which is what I do at a =
low lateral angle (around the bridges anyway). I have never been =
convinced of the need of downward tapping pressure at the bridges. For =
some reason this is one of the first things new technicians are taught =
and the thought of them going around with little hammers and pounding on =
pianos scares me. We straighten wire for control of damper and hammer =
contact and for quick stabilization of new strings. Perhaps having the =
wire come straight out of the bridge helps the string to vibrate in a =
more perpendicular plane even. I don't really know. After you take a =
few pianos apart you find that even in a negative bearing situation the =
angled pins hold the string tight to the bridge. If there is so much =
negative bearing that they don't then no amount of pounding will hold =
them there. But I guess that is another thread. Right now I need help =
getting out of this mess. I have finally accepted I have to pull the =
plate. So much for the quick restring of a fairly new instrument. =20
=20
Thanks, Steve Bellieu
---
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.427 / Virus Database: 240 - Release Date: 12/6/2002
Greg Newell
mailto:gnewell@ameritech.net=20
-------------------------------------------------------------------------=
-
---
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.427 / Virus Database: 240 - Release Date: 12/6/2002
-------------------------------------------------------------------------=
-
_______________________________________________
pianotech list info: https://www.moypiano.com/resources/#archives
---------------------- multipart/alternative attachment
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/6c/eb/1b/18/attachment.htm
---------------------- multipart/alternative attachment--
This PTG archive page provided courtesy of Moy Piano Service, LLC