Introduction
So you're in the museum,
measuring up a flute, and you're busily measuring lengths, diameters,
thicknesses etc. But then you realise, hey, I need to determine
what angle of rotation the keys are at relative to the line of finger
holes. How on earth am I going to do that in the field?
Relatively easily actually.
But we are going to have to go back to primary school....
Revision
How many degrees in a full
circle? 360º.
That's it? That's all
we need?
Method
1. Cut a thin strip of paper,
long enough to wrap right around the flute in the area the angle
measurement needs to be made.
2. Wrap the strip of paper
around the flute, overlapping where the reference point is. That's
probably in line with the finger holes.
If you want to be really
accurate, run a pencil line along the flute first using rule and pencil.
You can stick some tape to the flute first if you want to avoid drawing
on it. Alternatively use a pencil eraser to rub it off later.
3. Put a mark on both
overlapping points in line with the reference.
4. Without letting the paper
slip, put a mark at the angle you want to determine.
5. Remove the paper strip and
lay it flat on the desk. You have three marks.
6. Measure between the
outside marks. That tells us the girth (circumference) of the
flute. Let's call it C.
7. Measure between the the
angle mark and the nearer of the overlapping marks. That gives us
the offset, O.
8. Calculate the offset in
angle terms, rather than distance terms: Angle = O/C*360.
Example.
Lets assume we're measuring
the angle of the C key compared to the line of finger holes. We
follow the instructions above and find:
Distance between overlapping
marks, C = 78.5mm
Offset of C-key angle, O =
13.1mm
Calculation: Angle of offset
= 13.1/78.6 *360 = 60º
Conclusion
Now that wasn't so hard was
it? A really useful technique using virtually no equipment.
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