un-weighting

JIMRPT@aol.com JIMRPT@aol.com
Wed, 24 Jul 1996 16:15:07 -0400


Don;
"Did you mean parallel? The plugs must be cut from similar wood, with the
grain aligned with the grain of the wood in the key. If it is perpendicular,
the plug may come loose or crack the key."
Don Mannino RPT
74473.624@compuserve.com
Don, the following discussion assumes the same or similar woods in 'plug' and
keystick.
I think we are talking about the same principles and looking at them in
different ways. i.e. if the 'plug is installed with the grain parallel, and
in the same plane, as in the keystick, then expansion of the wood fibres will
occur in the same direction as in the keystick but at different rates due to
varying numbers of"hard and soft" rings between the keystick and the 'plug';
given enough difference between the two, the plug will get loose in one
extreme and be extremely tight in the other extreme. We all have seen what
just a slight amount of swelling, in some cases, it takes for leads corroding
to split the keystick. Of course many variables come into play with each
keyset being different.
  If the 'plug' is installed with the grain perpendicular (90 deg.)
to the grain in the keystick but in the same plane as the grain in the
keystick any swelling or shrinking of plug and keystick are counteracting
each other and many years later the plug will still be tight in the keystick.
Also even if the grain is a complete mismatch between 'plug' and keystick
there is less likelihood of the keystick being split by uneven swelling or
even extreme wet conditions. This due to the greatest movement of the plug
being from front of keystick to back of keystick, with the grain, and not
from bottom to top of keystick ,against the grain.
  I have used the perpendicular method for many years and other than a small
drop of glue rubbed on by finger at the bottom of one side of the
plug/keystick, after the plug is fit and installed and just for insurance, I
do not glue my plugs. I have never ran across a loose plug on any of the sets
that I have treated in this manner.
  I agree with Tom and Charles that little details count and each situation
is different and if there is going to be a great deal of weighing and
reweighing going on I would have to change my outlook. For simple weight
reduction on one set of keys I prefer my method to any other I have tried
  In any event Don if the same type of wood with a decent grain match is used
we should be able to use either method or perhaps even others that have not
been talked about and acheive satifactory results.
Just my opinion.
Jim Bryant (FL)
ps- I have some sugar pine and some spruce and intend to do some
experimenting on this subject because this thread has peaked my interest. The
wood has been in my shop for the same amount of time so there should not be
any significant differences in moisture content at the start. I'll post
results to the tech list when I finish.





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