[pianotech] Guess which pin...

[johnparham at piano88.com]

Rob,

Go to ptg.org and do the following:
-Log in
- Click on "Resources"
- Click on "For Technicians"
- Click on "Educational/Technical Resources"
- At the bottom of the page click on the blue "PTG Store" link
- Click on "Exam Resources"
- Click "NEXT" at the bottom of the page
- Here is where you will find the Technical Exam Source Book

-John Parham

> -------- Original Message --------
> Subject: [pianotech] Guess which pin...
> From: Rob McCall <rob at mccallpiano.com>
> Date: Sun, July 31, 2011 2:28 am
> To: pianotech at ptg.org
> 
> 
> Greetings,
> 
> I have a 1982 Kimball Console action in my shop. Many of the keys were sticking in the piano.  Looking at it in the piano, the problem didn't appear to be the keys, at all. It was definitely in the action. However, it was difficult to tell which center pin it was. At first it looked like the hammer butt flange pin needed to be re-pinned. So I did that.  It fixed it momentarily.  Then it started to stick again.  Looking at it, it looked like the wippen center pin might be the problem since it wasn't coming all the way back down when the key was released. Although, I wasn't clear if it was because the jack center wasn't resetting all the way, either. As the problems were over the entire upper third of the action to one degree or another, we agreed to have me take the action and work at it on my bench.
> 
> As it turns out, about 30 percent of the hammer butt flanges needed re-pinning. Also, about 20 percent of the jack centers had to be re-pinned.  Additionally, almost 50 percent of the wippens needed to be re-pinned. It was hit and miss, with some notes needing all 3 pins changed, others 2 pins, and some only 1 pin, while some remained unchanged. I ended up taking pretty much every hammer and wippen assembly off to evaluate all 3 pins.
> 
> It seemed very time-consuming, so my question is this...
> 
> What do you look at, or manipulate, to determine which pin is the culprit while the action is still in the piano or on the workbench? How do you test them all to determine the troublemaker without disassembling most of the action? 
> 
> Obviously, my method works very well, but, as I mentioned, it's very time--consuming. Any thoughts or insight is greatly appreciated.
> 
> Regards,
> 
> Rob McCall
> 
> McCall Piano Service, LLC
> www.mccallpiano.com
> Murrieta, CA
> 951-698-1875