Pinblock/Frame Separation

Ron Nossaman RNossaman@KSCABLE.com
Tue, 25 Jul 2000 18:04:06 -0500


>Hello List Friends. I ran into a pinblock separated from the frame on a 1967
>45" Baldwin Hamilton studio upright today.
------------------------

Hi Terry, 
Got trapped, did you? 


>I have four questions:
>
>1) -- Question: when I draw the pinblock/plate back to
>its original position against the frame, do I risk         cracking the
>plate?

Very probably not, though I suppose it's possible. See #3. Before doing
anything else though, I'd safety the thing with enough clamps along the top
so it won't move any further (don't close the gap yet, just insure that it
doesn't widen). Then I'd pull one lag in the middle, drill through, and
slip in my 3/8 carriage bolt, with the big washer that just fits over the
square section of the shank, from the back side (big footprint, minimal
wood crush) and get a lock washer and nut on it at the plate. Then I'd snug
up the nut until that center clamp wasn't really holding anything, and
remove the clamp. I do two or three this way (running the vacuum while
drilling) so I have the thing safetied by bolts before I start digging onto
the gap. I'll remove the rest of the lags too, except where the gap is very
narrow, leaving a couple of clamps, or not, as the situation strikes me.
Err toward caution.


>2) Today I let the tension down on the strings because of the BIG
>separation. 

Normally, I don't drop tension if it's already a half semitone low. It's
when it is close to pitch that I get worried, because that means that
someone has tried to pull it up with the separation already there. What you
did is plenty.


>3) There are broken chunks of wood (big splinters, etc.) debris lying
>between the pinblock back and the frame front. 

Instead of a coat hanger, I'd use a vacuum and a piece of music wire. It's
thinner, to get deeper into the separation, and springier, to flip those
little wood chips into your eye at a higher velocity - so be careful. A
thin spring steel like a soundboard cleaning tool with a hook ground in the
end, or one of the tools used to slip under car window weather stripping to
jimmy the locks, work very well too for the stubborn chunks. I like to
clean as much junk out of the chasm as possible, so I'm not levering the
plate into a bend in the other direction when I clamp it together. Then I
pour in plenty of Titebond, spread it around with my car theft tool or
spatula, and tighten up the clamps and nuts already installed, until the
gap closes and most of that "plenty" squeezes out to be mopped up
afterward. When the gap is clamped closed, I drill and bolt the remaining
lag locations, crank all the bolts down tight, saw off the extra bolt
length (inside), and clean up my rather considerable mess.  


>4) How long does this entire repair take you to complete (three service
>calls - one to diagnose and measure,         etc., a second to do the repair
>and leave clamps in place for epoxy to cure, and a third to remove clamps
>and pitch raise)?

I'm doing one this Thursday afternoon. It's a referral from another tech,
and I haven't seen it yet, so I don't know for sure what I'm in for, but
with a 1:00 appointment, I expect to have it bolted back together, pulled
to pitch, and tuned by 4:00. It will naturally need tuned again soon, like
with any major pitch change, but all the initial salvage work, pitch raise,
and tuning should be do-able in one trip. If the bolts won't hold it, the
glue won't either. Incidentally, I've had them come back close enough to
pitch that one tuning pass, sometimes even dropping the pitch slightly, was
enough for tuning. Don't count on it though. 


>Thanks for any and all constructive input!  :-)  (I like smiley and winky
>and frowny faces!)
>
>Terry Farrell

Well, not all at once. It's kind of confusing, and causes terrible cramps.

Ron N


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