Breakdown measurements

[Farrell]

Wim wrote: 

"In 25 years of rebuilding, I have never rescaled a piano."

And I have never NOT rescaled a piano. Why would you NOT want to rescale any piano you are rebuilding? IMHO, this would be like purposely never improving the geometry of actions during rebuilding - it should be one of the first things you look at!

Terry Farrell
  
----- Original Message ----- 
From: <Wimblees@aol.com>
To: <pianotech@ptg.org>
Sent: Friday, March 28, 2003 1:27 PM
Subject: Re: Breakdown measurements


> In a message dated 3/28/03 11:31:44 AM Central Standard Time, 
> kpiano@goldrush.com writes:
> 
> > Do I need the distance from the upper or front bridge pin to the hitch pin? 
> > What backscale dimension would the scale designer find necessary? The plate 
> > bearing points? 
> >    On the plain tri-cords do I need any more than just the speaking length 
> > and wire size?
> >   
> > Keith Roberts
> > 
> 
> Keith
> 
> The best and easiest thing to do is to send the bass strings to a company 
> that duplicates them. Be sure they stay in order. Cut them off at the tuning 
> pin. When you send them the set, be sure to include the name and serial 
> number of the piano. 
> 
> If you don't want to send the strings, you can make a paper pattern. It's a 
> little more difficult to do on an upright. The pattern should include 
> indentations of where the tuning pins are, the agraffs or upper hitch pins, 
> the windings, both at the top and the bottom of the strings, the bridge pins, 
> and the hitch pins. Again, on the pattern, write the name and serial number 
> of the piano. 
> 
> If you don't want to use either one of those methods, you can give them the 
> dimensions of the first bass string and the last bass string, including the 
> thickness of the core, and the measurements you indicated. It's a lot more 
> work on your part, and you run the risk that you didn't write down the 
> correct measurements. I would do this only as a last resort. 
> 
> As far as the plain wires, all you need is s the scale. Measure each string, 
> and indicate how many notes to a string size. You don't need any other 
> measurement, like the distance between the hitch pin and the bridge, etc. 
> 
> As far a rescaling, that's up to you. It might be more trouble than it's 
> worth, especially on an older upright, unless you are convinced the scaling 
> needs to be different. In 25 years of rebuilding, I have never rescaled a 
> piano. I made one up once, when I got a piano without any strings. 
> 
> Wim 
>