Broken agraffe

[Frank Weston]

OK,  anyone can remove a broken agraffe.  The real question is how does one
remove a broken agraffe with a broken thread extractor in it?  

For agraffe removal, I have found the following helpful:
Use a penetrating lubricant first.
Go slowly and carefully no matter what method you choose to employ.
Brass drills more easily than cast iron.
Gentle taps with a hammer can free a thread.
Turning in as well as out may free the thread, and can remove the agraffe
in the opposite direction.
A bigger extractor works better than a smaller one.
If all else fails drill out to the next size and tap.
If the next size is too big, grind the bottom of a replacement agraffe, tap
it and bolt it from the bottom of the plate.
Don't break the agraffe in the first place.

I do think I would stop short of using an acid that eats brass but not iron
(if there is such a thing).

Frank Weston

----------
> From: Rob Stuart-Vail <rob_sv@email.msn.com>
> To: pianotech@ptg.org
> Subject: Re: Broken agraffe
> Date: Tuesday, November 17, 1998 7:09 PM
> 
> Hi Oleg,
> 
> You've had some good responses, and the one I like best for attempt #1 is
> the reverse thread drill.  These are now available at a lot of good
hardware
> stores.  The one I used recently with great success is a "Drill-Out"
Micro
> Power Extractor #10 - M5 (left-hand drill bit, self-centering tip).  No
> company name on it, but I got it in a Tru-Value hardware store.  Even if
it
> doesn't just spin the agraffe out as you drill VERY SLOWLY AND CAREFULLY
it
> at least leaves a nice hole for some other tool.  Good luck.
> 
> Rob Stuart-Vail
> -----Original Message-----
> From: Oleg Isaac <oleg_i@club-internet.fr>
> To: pianotech <pianotech@ptg.org>
> Date: Tuesday, November 17, 1998 4:00 PM
> Subject: Broken agraffe
> 
> 
> >Hello,
> >
> >What is your favourite method of exctracting a broken agraffe in a
> >grand. (nothing is out)
> >
> >It is hardly blocked , I tried with degrip-oil and with propane torch (
> >it is accessible under the frame ) , and ... I broke my extractor in, I
> >am afraid the thread will be bad after I will pull it out.
> >
> >Is it easy to find replacement thread for the frame ? If I make a good
> >hole in the brass, will I be able to remove the resting brass threading
> >the new place ?
> >
> >Any idea welcome.
> >
> >Best regards.
> >
> >Isaac OLEG
> 
>