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<DIV><FONT color=#000000>Robert,</FONT></DIV>
<DIV><FONT color=#000000></FONT> </DIV>
<DIV><FONT color=#000000>Firstly, I am not knocking the idea as it =
appears to be
a vast improvement on the original but,</FONT></DIV>
<DIV><FONT color=#000000></FONT> </DIV>
<DIV>In an old PTG journal (about 20 years ago) there was an article =
with photos
about repairing cracks in iron frames. From memory, the =
method used
in that instant was very similar. Holes drilled and threaded and =
screws
inserted. The piano tuner who did this was from South Australia. =
(thats
the country down under)</DIV>
<DIV>Can't remember his name but maybe some oldtimer who has got all the =
old
editions of the Journal on the list will remember the article and be =
able to
look it up.</DIV>
<DIV> </DIV>
<DIV>I have found through my years of working on pianos that many
seemingly new ideas and concepts have been done before, and we are now
rediscovering them.</DIV>
<DIV> </DIV>
<DIV>Regards</DIV>
<DIV> </DIV>
<DIV>Tony Caught <A
href="mailto:caute@accessnt.com.au">caute@accessnt.com.au</A> </DIV>
<BLOCKQUOTE
style="BORDER-LEFT: #000000 solid 2px; MARGIN-LEFT: 5px; PADDING-LEFT: =
5px">
<DIV><FONT face=Arial size=2><B>-----Original =
Message-----</B><BR><B>From:
</B>Robert Goodale <<A
=
href="mailto:Robert.Goodale@NAU.EDU">Robert.Goodale@NAU.EDU</A>><BR>=
<B>To:
</B><A href="mailto:pianotech@ptg.org">pianotech@ptg.org</A> =
<<A
=
href="mailto:pianotech@ptg.org">pianotech@ptg.org</A>><BR><B>Date:
</B>Wednesday, 16 December 1998 3:33<BR><B>Subject: </B>EXTRA! =
EXTRA! Plate
Repairs- THIS COULD BE IT!<BR><BR></DIV></FONT>While at Yamaha an =
amazing
new method for repairing cracked piano was shared by another member =
of the
group. This is a completely new technique and is unlike =
anything
previously discussed. This group member also brought a video =
tape for
show and tell which put everyone in awe. Even LeRoy was =
dumbfounded
and is now wanting more information.
<P>This is no joke folks, read on...
<P>This crack repair method was developed originally for repairing =
cracked
cast iron engine blocks and other heavy machinery. It involves =
no
welding whatsoever. Instead a series of very specially =
designed screws
are inserted into the crack which quite literally pull the crack =
together
stronger than it was before. When the repair is complete it is =
almost
invisable. This may sound to good to be true but the tape =
demonstrates
this clearly. Two flat pieces of cast iron were fastened =
together in a
butt joint by a single one of these screws, and was then hooked on =
each end
with a heavy chain. The chain was then connected to a wench =
which
lifted a 350 pound engine block. The bond held =
perfectly. A
complete series of pins overlapping in a crack seals the crack =
permanently
and stronger than it was originally. On bench tests these =
repairs were
shown to be completely air tight at 80 PSI.
<P>Ok, so here's how it works. The screws are designed to dig =
in to
the cast iron. They must go into a pre-drilled hole using a =
special
bit. The holes are also taped. The secrete is in the screw threads =
which are
cupped sharply upward. The top half of the screw has a =
countersunk
collar which pulls tightly into the hole in the opposing direction =
of the
cupped threads. The screw is driven into the cast iron using =
an air
drill until the torque breaks of the head. The result is that =
the cast
iron is clamped tightly together *internally*. A series of =
these
screws are installed to follow the crack side by side. Then an =
overlapping series of screws are inserted in a second pass. The =
remains of
the torqued-off heads are ground away smooth. No welding, no
mess. This type of repair can even be made inside the piano =
without
plate removal. There are several types of these special screws =
which
can be used on various types of cracks, even on angles or in =
corners.
They are also available in various lengths. The video =
presentation was
extremely convincing and had us talking about it for the remainder =
of the
week.
<P>This group member's local chapter recently decided to try this =
repair as
a joint project. The inventor of this technique was personally =
present
and assisted in explaining and then demonstrated the repair. =
This
proceedure is brand new and this was the first such repair made on a =
piano. I think we can all pretty much expect to hear a lot =
about this
very soon.
<P>This repair system is called the "CastMaster" by a =
company
called Lock-N-Stitch. They do have a web page. Check it =
out and
be amazed.<A href="http://www.locknstitch.com/"></A>
<P><A href="http://www.locknstitch.com/">Lock-N-Stitch</A>
<P>Follow the link to "Information about Cast =
Master". After
you've read the text and looked at the pics, go to the link that
demonstrates the complete repair.
<P>Enjoy!
<P>Rob Goodale, RPT </P></BLOCKQUOTE></BODY></HTML>