Loose Pin Therapy

[Roger Jolly]

Hi Mark,
              When I have encountered a row of pins with terminal cancer,
invariably I find that the the block has started to delaminate. However I
have repaired a few PSO's by  removing the offending pins and generously
swabbing the holes with epoxy. reinstall the pins, leave for 24hrs to cure.
Lightly tap the pins to break the grip, (a precaution, I once snapped a
pin) and bring to pitch. I consider this a bandaid repair at best. 
A durable repair is as follows. Invest in a good set of plug cutters, and
make your own plugs from pin block scraps. Drill out the bad holes and
epoxy the plugs in to the block. drill for a standard 2.0 pin.
Your observation of straight line low torque problems are the same as mine,
over size pinning is fairly short lived, 4 or 5 years at best in this area.
With grands i would replace the block, with verticals I plug the offending
holes and over size pin.
Funny about the differences in the climate from Northern Canada and
Australia, However our humidity conditions are similar, 40 below Zero
moisture is hard to find In winter. At the University ( steam heated ) 10%
would be high. In Summer 40 above with 80% RH.
Regards Roger.






At 08:11 AM 23/02/99 +1100, you wrote:

>Pinblock problems here are usually terminal.
>Can I pose a supplementary question to the list?
>When the loose pins form a relatively straight line, wouldn't that indicate
>a grain weakness rendering the pinblock unsalvageable? "Therapy" in this
>situation would be difficult to guarantee. Oversize pins run the extreme
>risk of actually creating a crack that wasn't quite there yet, I'm afraid I
>don't hold (sorry, couldn't resist it) with products like Pin-Tite, and
>shimming holes (especially when there are quite few of them, doesn't appeal
>much either. A new plank would be the order of the day (not that you'd
>justify it on PSO or rock-crusher type upright).
>

Roger Jolly
Baldwin Yamaha Piano Centre
Saskatoon and Regina
Saskatchewan, Canada.
306-665-0213
Fax 652-0505