If you enjoy the technical side of things, please consider
buying my book "Left-brain
Lutherie" . Although no longer sold by StewMac, you can buy from LMII,
MIMF or directly from me.
Lutherie Spreadsheets
I enjoy trying to write spreadsheets which are useful in
challenging my understanding of a particular problem I'm trying
to solve when building ukuleles and guitars. I don't in any way view these spreadsheets as the
answer to a particular problem, or even examples of sophisticated
or economical programming, but rather a source of ideas which
others can improve upon or modify for their own particular
situation. The programs are as error-free as possible, but may
well contain mistakes; I would appreciate any mistakes found
being brought to my attention so that I can correct them and put
the new version on-line for others to use. Thanks in advance for
that... I now use Microsoft Excel for all my spreadsheets. It seems more
readily available to others. Further, since the files are all fairly
small, I've also chosen to keep them as Excel format rather than translate them
into *.ZIP files... There are many more spreadsheets associated with the
programs in the Technology section. Please look from page to page to find
out more about them.
- FRETCALC.XLS
(Microsoft Excel file)
(to download double-click or option-click)
Everyone has written a fret distribution calculation
based on the twelfth root of two and here's mine. It
grinds out fractional and decimal English measurements as
well as metric for any scale length. A usual number of
fret spacings are calculated, but of course more can be
added using the copy command.
- RESONATE.XLS
(Microsoft Excel file)
(to download double-click or option-click)
Articles in American Lutherie #s 1 & 13 by Allen talk
about various acoustic aspects of stringed instruments.
Among the formulas given are those for approximating the
air resonance for an instrument of given dimensions.
These calculations are approximate but useful in
obtaining a beginning understanding of how notes are
enhanced or not for different instrument shapes. The
frequency of note associated with each physical dimension
of an instrument are noted and a look up table is
available for noting which nearest notes relate to the
calculated frequency of the air resonance. It is
interesting to note that the lowest string frequency of a
given instrument is often very close to the air resonance
frequency.
- RELHUMID.XLS
(Microsoft Excel file)
(to
download double-click or option-click)
The relative humidity in the atmosphere has a significant
effect on what dimension a given piece of wood has
relative to what it was at another time and place. It's
not difficult to measure relative humidity if you have a
couple of thermometers or that neat little gadget from
Radio Shack. Here's a source of data to make tables and
graphs for using the temperature differences of wet bulb
and dry bulb thermometers.
- UKENOTE.XLS
(Microsoft Excel file)
&GUITNOTE.XLS
(Microsoft Excel file)
(to download
double-click or option-click)
These two spreadsheets give the frequencies associated
with fretted notes for the three smaller sizes of
ukuleles (UKENOTE.WQ1) and for the guitar and baritone
ukulele (GUITNOTE.WQ1). The baritone ukulele is strung
like the first four strings of the guitar. Additional
octave ranges are given for the G, C and A strings for
the ukulele because tenor ukuleles are commonly strung
with four, six and eight strings (see Sounds &
Strings).
- TOPTNSN.XLS
(Microsoft Excel file)
(to
download double-click or option-click)
This spreadsheet gives the nominal tensions per unit area
of the lower bout of the top and other data in both
metric and English units for the four ukulele sizes
(three within the tenor size for the three stringing
variants) and for a classical guitar. I feel that these
calculations can be useful for estimating bracing
thickness' when going from one size instrument to
another.
RODBUCKLE.XLS
(Microsoft Excel file)
(to
download double-click or option-click)
This spreadsheet calculates the pressure Pcrit applied by go-bar sticks
of varying diameter and materials properties.
StringtnsnWorth.XLS
(Microsoft Excel file)
(to
download double-click or option-click)
This spreadsheet gives the nominal tensions for each string for GCEA
tuning for soprano, concert and tenor ukulele sizes using the Worth Creation
strings.
StringtnsnNylGut.XLS
(Microsoft Excel file)
(to
download double-click or option-click)
This spreadsheet gives the nominal tensions for each string for GCEA
tuning for soprano ukulele sizes using the Aquila NylGut strings.
I enjoy writing these pages and hope that they are
interesting and useful to the reader. I'm slowing down in my building at
this time and still need to generate some income in order to continue to expand
this website with more useful articles. If this page was helpful to you
and you would like to make a $5.00 donation in order to have more pages like it,
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