Introduction
In our
previous article, we developed some theories about
what the bore should look like, and we think that the reconstituted tenons would
still fit in the sockets at each end. So how do we go about
reconstituting? Is there a plan? Not just one, as it turns out...
Plan A
Plan A is that I should subject it to some
normal playing, to see if, freed from its tenon wrapping constrictions, we might
see it starting to move spontaneously towards one of the shapes we predicted in
the previous articles. I must say, given the degree of compression, and
the time over which it has been built up, I'm not expecting miracles.
Plan B
If we see no sign of movement, we
could try some deep humidity cycling to emulate the passage of the years. But not attempt to
steam and reform it as I did with the two strangled flutes. The test would be
aimed at finding out whether just removing the constriction is enough, if given
time and seasonal variation (either in real-time or accelerated). If that
doesn't work, it won't prevent me from following the steaming and reforming
approach later.
Plan C
If Plans A or B show no
promise, I might ramp
it up a bit by simulating the accumulated effects of much longer playing over a
lot of time. We found in the test tenon case, that applying a damp rag to the inside of the bore was a
very
efficient way of injecting moisture. It's also interesting to speculate on
the difference between presenting moisture inside and out, as the weather does,
and just from the inside, as playing does. One can imagine in the playing
model that a wave of moisture propagates outwards through the instrument wall
followed by a wave of dryness. Whether this one-way propagation is enough
to produce a different outcome is something we'd need to discover.
Plan D
Plan D, involving steam, might be
resorted to if previous plans didn't produce enough movement. I steamed
the original boxwood strangled flute in the pressure cooker to make it limber
enough to straighten out. It might seem violent, but there is precedent.
Timber that has "collapsed" during kiln drying is sometimes recovered by
steaming for about 6 hours. Since cell collapse is a definite possibility
in this case, this approach seems not inappropriate.
Plan E
Plan E, might involve a "keeper".
Moisten the flute by one of the methods outlined above and, while it's swollen, introduce a keeper,
tapered to the desired bore shape. Allow the wood to dry out, and the
keeper should prevent it from assuming its old collapsed state. Repeat, gradually
insert the keeper a little more each time, as hopefully it eases the bore back
into the desired shape.
Making the keeper of course requires
making a decision between the various bore shape scenarios we talked about
previously. One could perhaps start with the most conservative, and if successful,
then aim for a more ambitious target. If I were going for a conservative scenario,
like "fix the tenons" or "two slopes", I think this could be achieved in one
treatment.
But, if I was holding out for something bolder, this might
require a series of treatments.
We have to recognise that, by
adopting the use of the keeper, we are abandoning hopes for miraculous
self-cure. But not quite abandoning hope for home or low-tech therapy -
the keeper could be something as crude as a hand-whittled dowel. You might
cringe and say, but what about the precision of the bore? Well, it could
hardly be less precise than it currently is, could it?!
There are interesting
practical issues in regards to use of a keeper. Once the flute
body has dried and tried to shrink onto the keeper, will I be able to
get it out? Hopefully, being tapered, it should just tap out.
Remind me about that word "just" a little later - I'll be
the one wielding the sledge hammer! Secondly, the
keeper may only be needed in the areas under the thread wrap. If
compression caused by the wrap caused distortion to propagate through
the section, presumably expansion in the same area will also propagate.
A sub-plot to be investigated.
Plan F
We're getting close to an "if all
else fails" scenario by the time we get to Plan F. We know from the
experience with the cocus strangled flute that a "steam-bending" approach will
straighten out even a thoroughly collapsed tenon back to the "fix the tenons"
scenario. But I don't think it will be enough to enable the
bolder approaches - the body wood is probably a bit thick to bend much in a
short time, even with steam to help. Still, the flute has got to play better without those
crumpled tenons!
Plan Z
If we can't at least correct the
distortion in the tenons back to the orange "two slopes" line, we can always
replace the tenons. That remains an option even if our experiment goes
horribly wrong. And we're not risking a priceless relic - the Potters made vast
numbers of flutes and they are well distributed around the museums of the world.
Most people would regard a flute in this condition as firewood.
As Bob
Dylan puts it in "Like a rolling stone", "When you got nuthin', you got nuthin'
to lose...". I hope we have everything to gain, and we won't come to Plan
Z.
An interesting thought on
Plan Z though. Just replacing the tenons will take us beyond the
conservative, "fix the tenons" scenario, perhaps even up to the red
"join the flat bits" scenario shown above. (A little reaming of
adjacent body areas would pull them into line.) But it would
probably not get us as far as the the boldest scenario dimensions. If we were serious about the
"Ignore the shrinkage" scenario,
we'd probably need to cut off the old damaged tenons, steam or whatever the body
back into shape, and then graft on new tenons. Woah, that's quite
an undertaking! But would anything less be "restoration", in the
musical sense? Sad too that a decision would have to be made
between restoration in the musical sense and restoration in the artefact
sense. Which is the more important when dealing with a musical
instrument? Hmmm, might leave that one to the philosophers!
Monitoring
Whichever plans I am forced to
invoke, I'll be closely monitoring changes. Having carefully measured all
the important dimensions (some of which are illustrated in the graph), I can
easily detect variations as small as 0.01mm. Since we are hoping for
changes in the 0.5mm to 1.3mm range, that's plenty of resolution.
I've also weighed the flute sections,
with laboratory scales capable of 0.01gm resolution and calibrated to that
precision. Monitoring the weight will tell me how much water it has
absorbed, and conversely, when it has re-equilibrated
with local or low-humidity conditions.
And I'm running a datalogger,
which will automatically record temperature and humidity variations in
the flute's environment, in case any dramatic changes there affect what
we are doing.
Conclusions
So, we have a target shape, or at least a range of
target shapes, identified in the earlier articles in this series.
And we have a plan, or at least a range of plans, by which we hope to
coax our poor mangled flute back towards the target shapes. So, I
think the time for measuring and wondering and musing and planning is
over, and the time for action is here. In our next article we'll
make the start.
On to Plan B, or
Back to McGee-flutes
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Created 8 May 2011
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