[pianotech] Pully keys

[David Ilvedson]

We will see how it turns out when John puts it up on his website.   

David Ilvedson, RPT
Pacifica, CA  94044

----- Original message ----------------------------------------
From: "William Truitt" <surfdog at metrocast.net>
To: pianotech at ptg.org
Received: 4/21/2010 3:12:19 PM
Subject: Re: [pianotech] Pully keys


>You called me superfluous?!  Why, them's fightin' words!! :-)

>I will respectfully disagree that taking this small extra measure is
>superfluous.  I have done it without such guide punchings, only to find that
>there was pilot error (no, I'm not talkin' about me!) and I did not get a
>straight line at the front. Small errors, but errors none the less.  The
>idea of using the punchings and glue is not mine, but I can't remember who
>to give proper credit to. 

>I hope your method will give you the results you seek.

>Will

>-----Original Message-----
>From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
>Of John Delacour
>Sent: Wednesday, April 21, 2010 1:28 PM
>To: pianotech at ptg.org
>Subject: Re: [pianotech] Pully keys


>I've ended up doing this job using the Schaff tool and the hornbeam 
>wrest-plate bushings, and, if I don't count the time spent working 
>out the job, it is quick, accurate and efficacious.

>The plate bushings are slightly larger than the socket made by the 
>tool and have a 2mm pilot bore running about half way down.  To 
>reduce the diameter I stuck a dolly wire in a Dremel type tool, runed 
>the onto the end and drew them across a sheet of abrasive paper -- a 
>few seconds work to get a perfect interference fit.

>I set the tool to cut the socket to a depth of a full 3mm, just to 
>clear the end of the original balance hole and make visible the 1/4 
>inch drilling beyond.  I then brushed the bushing with hot animal 
>glue and tapped it home in the socket, pilot hole down because that 
>end is chamfered.

>Then, with the key upside down in the vice, I cut the protruding 
>dowel flush with the line of the key using a Japanese saw and then a 
>paring chisel to reveal the pilot hole ready for drilling out with a 
>3.6mm drill and burnishing with an awl.

>I'll post pictures of the process in the next few days.  It looks so 
>far like a solid and durable job.  I have yet to lay the keys, but I 
>am not too anxious because, as I said before, the pilot shank on the 
>tool aligns itself to the _sides_ of the hole and slight pressure 
>towards the back of the key when starting the milling-out prevents 
>any influence from the crushed side.  Will Truit's idea is good but 
>time-consuming and --I hope I don't have to eat the word! -- 
>superfluous.

>When I look at the keys I'd give equal blame for the oval holes to 
>Steinway/Kluge for bad design, prima donnas for daft playing and 
>previous technicians for rough removal and replacement of the keys.

>On the old Steinways and most good pianos the balance pins are angled 
>backwards to enable the key to be removed by first raising the front 
>and then gently lifting off by the chase (button).  Already in 1916 
>Wolfenden was complaining that some makers had stopped this practice, 
>and he was right to complain.  Clumsy and thoughtless technicians are 
>in the great majority and the angling of the balance pins can 
>certainly minimize the damage they can do to the keys while making 
>things easier also for the minority.

>JD