Pinblock Separation Questions

[Clyde Hollinger]

Of those who responded to this thread, Ron's procedure is closest to what I do.  But
Ron, with your method what is the point of putting in any glue?  Since you are
tuning in the same visit, likely before the glue has set up, you are putting your
faith totally on the bolts.  And maybe that's okay.

My time is also usually 1.5 hours or so.  But I use clamps to pull the crack
together (which I think Ron does, too, but failed to include here) then snug up the
nuts.  I leave the clamps on for a couple days, then remove them and tune the
piano.  I use epoxy, not Titebond.

You lose a lot of time dropping the tension, then bringing it up again, tightening
coils, spacing strings, etc.  I wouldn't drop the tension unless the crack were
really wide.  Like Ron, I haven't had any of my repairs of this nature fail.

Regards,
Clyde Hollinger, RPT

Ron Nossaman wrote:

> >Also, any non-bionic technician willing to share how many hours they have
> >taken to do a repair like this - start to finish, not including pitch
> >adjustments and tuning (just clamping, drilling, bonding, bolting and cleanup)?
> >
> >Thanks.
>
> I'm old and fat, so I assume I qualify as non-bionic. I take off the lid
> and put a couple of monster clamps across the top of the back, drawing the
> gap in a bit. If I can close the gap, the clamps will hold it while I take
> out plate screws, drill through holes (3/8"), and install carriage bolts
> from the back. I use washers that will fit around the square shank at the
> head of the bolt to get a bigger footprint than the head provides. You can
> sink a 3/8 carriage bolt pretty deep into a piece of poplar otherwise.
> After the holes are drilled and I have bolts in place and have vacuumed up,
> I loosen the clamps enough to pour Titebond into the crack, helping it as
> necessary with a thin steel spatula purchased for just this sort of thing.
> Glue in, I crank the nuts (lock washer underneath) tight and use the bolts
> to pull the crack(s) together. Trim the bolts with a hacksaw, mop up the
> glue, pack up the tools, take them to truck, bring back my tuning case, put
> the lid back on, pitch adjust and tune the piano. I haven't lowered the
> pitch to bolt the back, so the thing is often not far off, and I don't have
> coils and such to mess with.
>
> Takes somewhere between an hour and an hour an a half for the repair, plus
> whatever the tuning takes, and I'm done in one trip in usually around 2.5-3
> hours total.
>
> No failures yet, that I know of.
>
> Ron N
>
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