Pinblock/Frame Separation

[Farrell]

Hi Bill. Thanks for the input. No, I have not done this repair yet. The
piece of hardwood for the carriage bolt stability sounds like a winner. Ron
N. suggested using 3/8" dia. bolts. The 8 counter-sunk-headed plate screws
along the top of the plate that I will be replacing with the thru-bolts were
5/16" dia. Do you think the nut on the plate side of the carriage bolt will
sit alright covering the counter-sunk feature in the plate? Oh, and hey,
lunch was cool!

Terry Farrell
Piano Tuning & Service
Tampa, Florida
mfarrel2@tampabay.rr.com

----- Original Message -----
From: <Bdshull@AOL.COM>
To: <pianotech@ptg.org>
Sent: Wednesday, July 26, 2000 5:26 PM
Subject: Re: Pinblock/Frame Separation


> Hi, Terry:
>
> With all the great posts on this subject so far, you have probably done
this
> job already.  A couple things from my own experience:
>
> On the one job I have done with so much separation (as least 1/2"), I
found
> that I could get the crack closed, but it took time.  My pipe clamps bent
> from the pressure - I learned later it was mostly from my impatience.  If
you
> use a slow setting glue you can borrow several hours for the gap to close,
> and it should close.  As Newton said, closing the gap IS important for
> downbearing.
>
> If the back has pulled up and tilted - common in these situations - you
may
> want to try to pull it down with long bar clamps fixed on the top and
bottom
> of the back.
> Many of these repairs close the gap but leave a gap between the
> liner/pinblock assembly and the top of the posts.  Ideally this will also
be
> closed, top and bottom of posts.  Since some pianos have a softwood liner
in
> back (I think some Baldwins do, I know some have hardwood), I have used a
> steel plate or at least a hardwood liner to support the tee nut or
carriage
> bolt.  Otherwise it pulls through and is pretty ugly - more important, you
> have to deal with the factor of the bolt pulling through the softwood
while
> you are trying to pull the crack closed.  Your clamps help - they do most
of
> the work, of course - but what is the point of the long bolts if they can
> still pull through a little more?  Better support them with hardwood
inserts.
>  Next time I might make circle inserts in place of the liner at the bolt
hole.
>
> Sure enjoyed meeting you - that dinner with Brian and Conrad was
> unforgettable in more ways than one - I hope my restaurant faux paus is
> forgiven - you bore the brunt of it, I am afraid.
>
> Hope this repair was a lot of fun!
>
> Bill Shull, RPT
> University of Redlands, La Sierra University, Riverside City College
>
>