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Letter: Glue, Chemistry, Etc

Letter: Glue, Chemistry, Etc.

by Lloyd Scott Ogelsby

Originally published in American Lutherie #11, 1987 and Big Red Book of American Lutherie Volume One, 2000



Dear Tim,

The history of your Guild closely parallels the history of the Pyrotechnics Guild International Inc., but your publication and membership are twice the size of ours. Who’d have thought we could find over a thousand folks that roll their own fireworks! The PGII is now the largest fireworks organization in history and we have more pros than the pro organization. Come to our convention, I promise you the best fireworks on planet earth and enough of them. It’s a lot of blasts.

Due to back and neck injury, what is left of me has taken up violin making. Until August 14th last year I had quite a laboratory at home, doing research on varnish and wood treatment. The house burned down — gone.

It’s easy to distract an old chemist with ancient chemical puzzles. For the last two years I had made hundreds of these funny organic polyester blends that form glass structure polymers that are traditionally called natural resin and oil varnishes. I played with everything from boil your own sink oil to road paint phenolics, phthalic ester resins, and isophthalatics, and had spent a fortunes on resins and oils in a shotgun approach to educating myself on phytochemistry and what to preserve and pretty up wood with. Fortunately the chemistry is simple, if very complex in the number of products that the four principle reactions can make.

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Dalbergia Nigra and Friends

Dalbergia Nigra and Friends

Luthier and author Cumpiano interviews famed wood scientist Bruce Hoadley

by William Cumpiano

Originally published in American lutherie #1, 1985 and Big Red Book of American Lutherie, Volume One, 2000



For over four hundred years, Dalbergia nigra has been considered the crown, jewel in the luthier’s creation. Its color, figure, and vitreous hardness has made it the sine qua non in the luthier’s inventory of raw materials. And so it has been among cabinetmakers: a book published in the late 1700s characterizes Brazilian rosewood as the “queen of the hardwoods.” Today a luthier can tack on something like $500–$800 to the sale price of a new guitar simply for the purchaser’s privilege of owning one made from Brazilian rosewood, never mind whatever additional qualities it may have. Part of this is unquestionably due to the material’s unique suitability and beauty but also is due no doubt to its great scarcity.

Manuel Velázquez, perhaps one of the greatest living classical guitar luthiers, bemoaned this fact and told me that during World War II, when he was a salvage carpenter in the Brooklyn Navy Yard, he was required to dismantle ten-foot mess tables and benches made from two- and three-inch thick Brazilian rosewood — and this was on troop ships. He began his career in guitar making taking scraps home with him. When I started my own career about thirteen years ago, these same Brooklyn docks held piles of enormous Dalbergia nigra logs stretching as far as the eye could see. The docks are empty now. Back then a set of Brazilian cost $35. Today a set of lower grade Brazilian can run $150, the better stuff up to $200. For the equivalent of less than one board foot of volume, this means Dalbergia nigra is among the two or three most expensive hardwoods in the world.

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The Bluegrass Dobro

The Bluegrass Dobro

America’s Second Native Instrument

by Bobby Wolfe

Originally published in American Lutherie #5, 1986 and Big Red Book of American Lutherie, Volume One, 2000



There is a little ditty known as “The Duck Principle.” It says: If it looks like a duck, if it walks like a duck, if it quacks like a duck, then it must be a duck. Well, since the Dobro only looks like a guitar, and even in this respect with significant differences, and doesn’t qualify in the other ways, I say it’s not a duck.

Seriously, in my opinion, the mechanically amplified instrument known as the Dobro does qualify as America’s second native instrument.

This article is designed to acquaint you with the Dobro and to provide information on common repair and setup needs of the instrument. Today, in addition to the members of The Original Family building the original instrument, there are many individuals building their versions. Most of these people have their own ideas and opinions about what works best. Therefore, I am not presenting my ideas, experiences, and working practices as the “last word.”

First, let’s define Dobro. It is a registered brand name that is now also used generically to describe most resonator-type guitars. The name comes from the Dopera (Dopyera) brothers. There are five Dopera brothers. There are five letters in Dobro. The word dobro means “good” in their native Slavic language. Take your pick!

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Basics of Air Resonances

Basics of Air Resonances

by W.D. Allen

Originally published in American Lutherie #1, 1985 and Big Red Book of American Lutherie Volume One, 2000



Stringed musical instruments with soundboxes typical of the guitar and violin families have many internal air resonances. The resonance with the lowest frequency is called the Helmholtz resonance, and its importance to the quality of the instrument is appreciated. The resonances with higher frequencies have been referred to by different names: higher Helmholtz, cavity modes, or standing wave modes. These resonances have been measured and documented for several different instruments, but there seems to be little information on their controlling parameters.

The intent of this article is to give the instrument builder some understanding of the air resonances, what parameters establish the frequencies, and some insight into the potential for using this information to make better instruments. A minimum-math, pictorial approach with approximation and rounded-off numbers will be used. Showing the effects of the controlling parameters is the objective, not the absolute value of a number.

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Area Tuning the Violin

Area Tuning the Violin

by Keith Hill

Originally published as Guild of American Luthiers Data Sheet #283, 1984 and Big Red Book of American Lutherie Volume One, 2000

See also,
Hints for Area Tuning the Violin by Keith Hill



Announcements of “discoveries” of the “secrets” of Stradivarius usually are not worth the ink used to print them. When they appear, everyone reads them with the customary curiosity. Then away they are filed along with the hundreds of other such claims. They get dredged up again when someone writes yet another book on the violin. Mindful of this possible fate, I would like to offer an explanation of a discovery that I have made. It is not of the “secrets” of Stradivarius; rather it is, I believe, the acoustical system utilized by the ancient Italian violin makers.

The system is simplicity itself. It is possible for anyone who understands it and has normal hearing to use it. Moreover, it requires no measuring equipment save the ears and possibly a monochord. Furthermore, the thicknesses and their inexplicable variants, which so annoy our modern sense of decency when we observe them in the finest violins by Stradivari and Guarneri, occur naturally as a result of this system. Because it is so simple, it is, of course, the last place one would think to look for the answer. I expect that once you are equipped with the following information, you will go to your nearest antique Italian fiddle and look to see if what I am saying is actually there.

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