Agraffe Repair Technique

[David ilvedson]

Tom,

The fishtail ground screwdriver nearly always works if you grab 
on with a small vice-grip and tap while you are applying 
pressure counter-clockwise.  

David Ilvedson, RPT

Date sent:      	Tue, 07 Sep 1999 00:11:51 -0700
From:           	Tom Cole <tcole@cruzio.com>
To:             	pianotech@ptg.org
Subject:        	Agraffe Repair Technique
Send reply to:  	pianotech@ptg.org

> It was a familiar sight, today: a 1926 S & S "B" with all 3-strings of a
> tenor unison holding its damper aloft. Familiar, but having read here
> and heard elsewhere the many tales of broken easy outs (and hearts) that
> have resulted from this seldom-performed task, the prospect still gives
> one pause. It is a job that needs to be done right the first time. And I
> don't have time to do it right the second time.
> 
> The major problem with easy outs, as I see it, is that if you drive a
> tapered tool into a hole drilled in an orphaned stud, you will tighten
> the fit of the brass fragment in the hole. The more you force it into
> the stud to get a bite, the less it will be willing to come out, ala a
> Chinese finger puzzle. The trick is to get a purchase without swelling
> the brass.
> 
> The first thing I tried, after soaking the threads with Liquid Wrench,
> was to tap with an awl and hammer, the awl pointing in a somewhat
> counterclockwise direction. Sometimes this will break it loose, after
> which the screwdriver ground to a fishtail shape is useful to spin it
> free. It didn't budge. The two-pronged screwdriver was equally useless
> against decades of oxidation.
> 
> Plan B, I thought, would involve drilling a hole for an easy out.
> Although my entire collection of easy outs was conveniently squirreled
> away in my shop, I drilled the hole anyway, hoping that something in my
> several toolkits would volunteer for duty. 
> 
> I drilled the hole as vertically and centered as I could, guided by a
> well-centered dimple from the awl, and I drilled it all the way through
> so that I would have some hope of tapping out a broken extractor or
> drill bit from below. 
> 
> A tool box search produced a rarely-used, 3-cornered, Hale reamer ground
> for a combination handle. The part that fits in the handle is the usual
> 1/4" diameter, then the shaft steps down to .167" and in the final 3/4",
> three flats are ground, coming to a sharp point. A similar-sized
> screwdriver could be modified with a grinder.
> 
> I tapped the tool firmly into the hole with a hammer to get a good bite.
> After attaching the combination handle, I worked the tool back out of
> the hole and reinserted it without tapping but applied some force with
> hand pressure. Grabbing the shaft with vicegrips, I could then start to
> twist the tool, first in one direction and then the opposite, again and
> again with increasing pressure, until the stud began to move.
> 
> And move it did. Once it was broken loose, I had no problem backing it
> out the rest of the way.
> 
> I finished the job in the usual fashion except for one thing: I left the
> strings in the old agraffe to keep them in order. Since they passed
> under the bass strings, I was glad not to have to wrangle with these
> wriggly wires.
> 
> Tom
> -- 
> Thomas A. Cole, RPT
> Santa Cruz, CA
> mailto:tcole@cruzio.com
> 
> 


David Ilvedson, RPT
Pacifica, CA
ilvey@jps.net