BUILDING BLOCKS The importance of wood choice & preparation in instrument making
By Heather K. Scott
“Burying wood in manure,” says Violin Society of America Award–winning vio- lin maker David Fol- land with a laugh when asked if he’s tried any unusual wood-preparation tech-
niques. “It is not recommended,” he adds. The process of selecting and preparing wood prior to making an instrument can be personal—even philosophical—for many luthiers. And some experiments get down- right odd. Explaining the novel technique, Folland says, “It was done because there was some ammonia fuming that happened, and possibly some useful fungal growth in the wood—don’t know, I am just guessing. It was back when I was very young and new to vio-
lin making, and I would just try anything.” Eccentric experiments aside, most luthiers have a particular system when approaching the raw materials of their trade. Wood selection and the way the wood is pre- pared before it takes the form of an instru- ment define the characteristics of the finished product. It is no wonder, then, that luthiers treat the process with care and dili-
The wood-selection process can be difficult and even agonizing for many makers. As Fol- land explains: “Everything else that I do on the instrument springs from the choice of the wood I use, and so I view this step as perhaps the most important in the whole process.”
Most violin makers begin by assessing player needs to determine an instrument’s ideal characteristics. For Collin Gallahue, winner of the 2014 Violin Society of America International Instrument and Bow Making Competition’s gold medal for Violin Tone & Workmanship, and former workshop fore- man for famed, New York–based string instrument maker, Samuel Zygmuntowicz, tonal and physical goals for the instrument
are key. “These goals are directly informed by conversations with the player and by lis- tening to him play on his existing instru- ment as well as others that I have made,” says Gallahue.
“Establishing a clear understanding of what the player seeks in a new instrument informs both my choice of model and the materials that I select for the project.”
Once a player has described his needs and preferences, the luthier’s attention shifts to the specific characteristics of the wood that will produce the desired tone. Folland says he usually tries to reproduce the sound of an existing instrument, and selects “wood with a similar density, speed of sound, place of ori- gin, and grain or flame pattern that I think will give me those characteristics.”
Paul Crowley, winner of the 2014 Violin Society of America Competition’s Certificate of Merit, says specific wood characteristics speak strongly to him. “I look at the grain width, particularly with spruce. I want a grain spacing of about 1.2–2mm in width,” he says.
Additionally, the specific gravity (the ratio of the density of a substance to the density of a reference substance), is vitally important.
“I have a narrow bandwidth of wood that is acceptable: My happy place for spruce is .37–.4g/cm3 and for maple between .54–.6g/ cm3,” Crowley explains. “I’m somewhat of a traditionalist and this density range is in the same range of the wood used by many of the old masters.
“I make sure that the piece is well quar- tered and that the split runs straight. When choosing maple, I’m also looking for a strong figure or flame—this is more of an aesthetic quality and I’m looking for wood that is striking or interesting to look at,” Crowley adds.
“Beginning with excellent materials is critical,” says Gallahue. “I look carefully at
the cut of the wood to assess if it is perfectly quartered. I also want to see that the split runs in plane with the billet and is free of twist and irregularities. I look for fine annual growth and a consistent, regular flame. The split, cut, and grain of the wood greatly influence the material’s strength.”
Assessing specific wood characteristics can become intuitive with enough experi- ence. This is the case with Jonathan Cooper, an award-winning, Maine-based luthier who has been making instruments for over 30 years. “If I’m choosing wood for someone, I like to test it by holding it so I can feel the weight, density, and elasticity.”
“Starting out with the right piece of wood is incredibly important. If a piece of wood is too heavy and dense, or too light you’ll never be able to build a great violin,” Crowley says. “It’s like cooking—if you start out with the best ingredients, you have a much better chance at making a tasty stew.”
Not only is the type of wood important to vio- lin makers, but also where it grows. Folland likes to use spruce and maple. “Sometimes the back maple is slab,” he says. He likes spruce from Italy. “But the maple is more var- ied, mostly from the Balkan area, but other places in Europe as well. With violas, I do sometimes use maple from the northwest also,” he adds.
“I use mostly European or Carpathian Spruce (Picea abies) and maple (Acer pseudo- platanus),” says Crowley. He sometimes selects Englemann spruce for tops as well as willow and poplar for viola and cello backs. “I will occasionally use wood from North America—willow or poplar for a cello or viola back, or Englemann spruce for tops— but 95 percent of the wood I use is sourced from Europe,” says Crowley.
Cooper, too, prefers European wood and considers spruce from Northern Italy to be his favorite. “Hazel spruce also has beautiful flaming,” he says. He also personally cuts
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and uses maple and poplar from his home state and seasons it for five to ten years before using it. Cooper purchases wood from late luthiers’ estate sales as well, knowing that often wood left behind by great makers is top quality.
Gallahue also likes spruce from Northern Italy. “I primarily use spruce from the Dolo- mites and maple from Bosnia and surround- ing countries.” But he’s found Engelmann spruce from British Colombia that he likes as well.
It’s like cooking—
if you start out with the best ingredients, you have a much better chance at making a tasty stew.
Preparing selected wood for instrument making is a personal process—with specific steps that are singular to each maker’s style. However, there are three main steps every maker must follow:
1. The wood needs to be seasoned.
Seasoning, or drying, of wood prior to build- ing is incredibly important. “Allowing your materials to season properly helps with sta- bility in the finished instrument,” explains Gallahue. Cooper agrees and considers this process as a key step in the instrument- making process. “Much of my wood has been seasoned at least 20 years, some pieces are as old as 100 years or more.”
“I like to season my wood for a minimum of five years—the longer the better,” says Crowley. The wood needs to reach equilib- rium with the environment to be dry and stable.
is an important consideration when seasoning wood.
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JOSEPH GRUBAUGH AND SIGRUN SEIFERT’S STUDIO—MICHAEL AMSLER
Folland prefers to buy wood that is already fairly seasoned, but also seasons wood in his loft, the driest part of his shop. “Ten years is good for seasoning, but remember, del Gesù used wood that was very fresh,” he says.
2. Wood should be stored appropriately.
“The environment in which wood is stored has a significant influence on its seasoning and on how quickly it may be suitable for use. My wood is stored to maximize airflow around each piece and exposure to natural sunlight. The wood is subjected to the hot, humid, summer air and to the very cold, dry winter climate as well. I find that allowing the wood to move with these natural extremes results in a very stable material, which in turn imparts stability to the finished instrument,” says Gallahue.
“My wood is stored in a loft above my stu- dio, in many racks that I can easily access,” says Folland. “Each piece is marked, on both halves, with its density, speed of sound, date cut, where it was cut, whether it was soaked or not, and when I bought it.”
Cooper stores his wood in the top floor of his studio. “I put a fan on it right away to get air moving and to help it keep its color.”
3. Wood needs to be sawed, split,
“After the wood has been allowed to season for at least five years, I prepare it by sawing the split quarter in half, and then joining those bookmarked halves—unless I’m using a one-piece top or back. This newly joined
piece is flattened on the bottom and then the arch is ready to be carved,” says Crowley.
The wood is subjected to the hot, humid, summer air and to the very cold, dry winter climate as well. I find that allowing the wood to move with these natural extremes results in a very stable material, which imparts stability to the instrument.
methods are some of those used by the mak- ers we interviewed:
Folland has done a fair amount of soaking wood, using the Milo Stamm method (and has presented his results at the most recent VSA convention meeting). The Milo Stamm method dictates a months-long soaking pro- cess followed by a period of storage with specific parameters designed to maintain moisture and encourage the right kind of bacterial growth to disintegrate sugars in the wood.
The process is meant to result in lighter, more flexible wood. “The more I do it, the more I like it,” Folland says of the method. “But I still can’t say definitively that it improves the sound. What it does do, for sure, is take a piece of maple that is heavier than you want it to be, and lighten it and move it into a range that makes it a good piece of wood to use,” he says.
Boiling and Torrefaction
Cooper boils his maple wood, “too ensure that the sap is out of it,” before beginning an instrument-making project. “I don’t do this with spruce, though,” he adds.
Cooper has also been trying a process called torrefaction, in which his wood is put into a kiln and brought up to a certain tem- perature.
Then the oxygen is removed from the kiln. “The process creates a stable, stress-free wood that is darker and more opaque.”
—Collin Gallahue fter wood has been selected
and seasoned, makers use a variety of techniques to pre- pare the wood for instru- ment making. Prior to cutting or shaving down the wood, the following
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