Hi,  Luke Myers made an interesting comment in his note about restoring
his Steger player action [16.12.15 MMDigest].  He mentioned that the
screw holes for the pneumatics were becoming stripped out so that they
no longer held the screws tightly.  That's a consequence of putting the
screws in and out several times incorrectly.

When the screw (with male threads) was originally installed, it 'formed'
a matching set of female threads in the wood.  When the screw is removed
the first time, it leaves the wood in the form of those female threads.

If you casually re-install the screw, it will usually form a new set of
female threads (slightly offset from the first set of threads) by pushing
the wood fibers around a bit so that they fit into the male threads on
the screw.  If you do this a few times, it will eventually grind up the
wood next to the screw enough that the fibers will no longer hold the
screw in place.  It's the same as cross-threading a machine screw except
that it's not as obvious.  With a machine screw, the screw will jam and
it will be much harder to turn, so you'll notice it.

Here's the proper way to re-install a screw.  Place the screw loosely
into the hole.  Now, turn the screw carefully counter-clockwise until
it drops slightly into the original threads.  Then turn it clockwise to
tighten the screw.  If you do this a few times, it will become obvious
when you match up with the original threads - and it will become
automatic.

I've had a Castlewood organ for about 15 years and the sides are
attached with several small wood screws.  I've taken the two sides off
and on at least 100 times to show people how it's built inside and the
screw holes are still just fine.

If I'm concerned about the condition of screw holes in wood, here's
what I do.  When I take the screw out for the first time, I put a couple
drops of CA adhesive into each hole and let it dry/harden completely.
This hardens the wood fibers and creates permanent threads in the wood.
Then I'm careful about re-installing the screw so that the threads
match each time.  In fact, I've even produced threads for a machine
screw by drilling a clearance hole first, making a thread in the wood
with a metal tap and then hardening the wood threads with CA glue.

By the way, if you want to try to rescue those stripped holes in the
wind chest, try putting a couple drops of CA glue in each hole and let
it dry for an hour.  Then try installing the screw.  Or you can drill
out each hole and glue in a small dowel and start from scratch.

Regards,
Craig Smith - in snowy western New York