[pianotech] Whistlin' Wixey

[William Truitt]

Hi Ron:

Yes, I have seen your photo, and had actually copied and pasted it along
with others into  a Wixey Word document.  I believe you simply turn your
gauge on its side where the shorter spacing between the feet is, zero it and
take your reading.  I made mine more like Jim's because that's what I had
laying around the shop.  

I would rather ask a stupid question than not ask the question that I should
be asking because I do not understand something.  Do the comparative
deviations you describe correspond directly to the the values of .5 degree
to 1.5 degrees so often given as the values we want to achieve in a strung
piano?  My goal here is to get to apples to apples.

I understand that the loading of the board is the combination of both front
and rear bearing loads.  Still, Frank Emerson earlier gave an example on
Baldwins with a significant mismatch between front and rear bearing where it
would be important to know.  For me, it is useful at this early juncture in
my bellyman career (I've only done 2 boards) to help me understand where my
feet are, and giving me the comfort that I have not built into the mix a
serious mismatch between front and rear.  I'll take your point that we
should not make it any more complicated than it needs to be otherwise.  

Thanks,

Will



-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Ron Nossaman
Sent: Wednesday, August 11, 2010 10:22 PM
To: pianotech at ptg.org
Subject: Re: [pianotech] Whistlin' Wixey

William Truitt wrote:

> What should I zero the gauge to?  There seems little in a piano that is 
> flat and level to serve as a meaningful reference.  I want a proper 
> reference point to zero to, so that the values will accurately reflect 
> the angle of the string.  What are others using as their reference?

If you're willing to do a lot of unnecessary math, you can 
zero to anything at all and calculate deviations for 
comparison of all the string segments of interest. Or you can 
zero on one of the string segments and get comparative 
deviations of the other segments in that unison directly.


> I made a gauge similar to Jim I's.  Foot spacing is too long for rear 
> angle check in high treble with rear duplexes.  I will make another base 
> with shorter feet.  Have others made another base with shorter span 
> between feet to use in the treble?

I've posted a photo at least three times, the last less than a 
month ago. Look in the archives on 7/13/2010.


> Won't the relationship between the front and rear angles be affected by 
> how carefully the bridge top is planed down to the desired height when 
> setting bearing at the bridge?  That is, how careful one is to not plane 
> down too much off the front side or back side of the bridge.

First, you have to determine how critical the comparison 
between front and rear bearing angles really is, and how that 
affected all those rebuilds you did before you had a Wixey to 
measure them.

Ron N