Posted on October 10, 2025October 10, 2025 by Dale Phillips A Summary of John Greven’s Voicing Method A Summary of John Greven’s Voicing Method by Mike Doolin Originally published in American Lutherie #114, 2013 John Greven has been building guitars for fifty years, and has single-handedly built over 2200 guitars in that time. Doing the math, that means he averages close to a guitar a week. Given that kind of efficiency, it’s not surprising that his methods for controlling the sound of his guitars are simple and direct. He’s distilled the huge number of variables down to the handful that he believes are most important, and has evolved testing methods that take only seconds and require no measurement tools. While John is a trained scientist, and does speak of the scientific aspects of guitars and wood, he’s quick to point out that his methods are not scientific, but intuitive and experiential. This is a major problem in documenting his methods: in a sense, you have to be John Greven to fully understand them. They rely on John’s vast experience in building thousands of guitars, and playing those guitars and thousands of guitars by other builders, and on his “photographic” memory for sound, and the database of sounds that his experience and memory have created in his head. Moreover, sound is not accurately describable in words, and tactile sense is not accurately quantifiable. Become A Member to Continue Reading This Article This article is part of the Articles Online featured on our website for Guild members. To view this and other web articles, join the Guild of American Luthiers. For details, visit the membership page. MEMBERS: login for access or contact us to setup your account.
Posted on October 9, 2025October 9, 2025 by Dale Phillips Calculating Guitar Side Height Calculating Guitar Side Height by Mike Doolin Originally published in American Lutherie #75, 2003 and Big Red Book of American Lutherie Volume Seven, 2015 Back in American Lutherie #58 (Big Red Book of American Lutherie Volume Five), Jon Sevy published the article “Calculating Arc Parameters” which described how to calculate the radius, length, or depth of a curve. I’ve used these formulae extensively ever since for radiusing fretboards, making dished workboards, calculating neck angles, and even nonlutherie shop tasks. Recently it occurred to me that one could use them to calculate the height of a guitar’s side at any point. If the guitar has a spherically domed back, the back falls off from its highest point in an arc in every direction, as in the photo. This “high point” is effectively the North Pole of the sphere from which the back arch is taken. If we assume a top whose perimeter is all in the same plane, as in Fig. 1, that plane intersects a line of latitude on that sphere. The high point is therefore the point on the back which is farthest from the plane of the top perimeter. All measurements of side height are then distances between that plane and the surface of the sphere of the back arch. I adapted Jon’s formula to calculate the falloff from the high point on the back to any point on the side: Become A Member to Continue Reading This Article This article is part of the Articles Online featured on our website for Guild members. To view this and other web articles, join the Guild of American Luthiers. For details, visit the membership page. MEMBERS: login for access or contact us to setup your account.
Posted on July 7, 2024May 14, 2025 by Dale Phillips Waterborne Solutions Waterborne Solutions by Mike Doolin and John Greven from their 2001 GAL Convention demonstration Originally published in American Lutherie #73, 2003 Doolin: Waterborne finishes and methods of working with them are constantly evolving. New products come out every year and old formulas are continually being updated. This workshop is like a snapshot of what John and I were doing at the time, and our techniques have continued to evolve. We trade techniques back and forth and share our results with new products as they become available. We never seem to be using exactly the same products or techniques; this just goes to show that there is no perfect finish product or technique yet. However, John and I agree that the products which have become available in the last few years are finally up to the task of producing a finish worthy of a fine handmade guitar. Before we get into the nitty-gritty, I want to talk about what waterborne finish is. First, think of lacquer and shellac. Both lacquer and shellac are resins dissolved in solvent. Spray it on, the solvents evaporate out, and that’s it. There’s no structural cross-linking reaction going on. Anytime after the finish is dry, you can use lacquer thinner to wipe the lacquer off the guitar. The same is true for pure shellac, which is always soluble in alcohol. That’s useful for a finish which will be rubbed out, particularly if you’re going to be touching up at a later time. You can melt that coat in. Otherwise, if the subsequent coat has to stick by a mechanical bond, you get a witness line if you sand through the top coat. One of the advantages of the new waterborne finishes is that they seem to do that — to burn into their previous coats. That’s one of the things we’re looking for. Become A Member to Continue Reading This Article This article is part of the Articles Online featured on our website for Guild members. To view this and other web articles, join the Guild of American Luthiers. Members also receive 3 annual issues of American Lutherie and get discounts on products. For details, visit the membership page. MEMBERS: login for access or contact us to setup your account.
Posted on June 6, 2024May 28, 2025 by Dale Phillips Questions: Gibson Firebird Plan Questions: Gibson Firebird Plan by Mike Doolin Originally published in American Lutherie #75, 2003 See also, Questions: Gibson Firebird Plan by David Riggs Marc Vermeiren from cyberspace asks: I’m searching for a plan of a Gibson Firebird. Mike Doolin of Portland, OR responds: I’ve never heard of a published plan for a Firebird. It’s a Gibson solidbody that came out briefly in the ’60s and has occasionally been reproduced since then. It wasn’t terribly popular. The pickups were different than normal Gibsons, but I think Seymour Duncan makes a Firebird replacement pickup. I’d say your best bet would be to find a Firebird and trace the body shape. ◆
Posted on June 6, 2024January 16, 2025 by Dale Phillips Letter: Catalyzed Polyester Finish Letter: Catalyzed Polyester Finish by Mike Doolin Originally published in American Lutherie #85, 2006 I’ve switched from waterborne finish to catalyzed polyester. Why? Hardness and speed. Poly provides the durability to which most steel-string players are accustomed. It’s basically 100% solids and cures by catalysis instead of evaporation, so it doesn’t shrink over time. I can rub out a finish after five days cure, and a year later it will look just as good. But those qualities come at the price of toxicity and flammability. I now have a commercial spray booth with an explosion-proof room around it, and a supplied-air full-face respirator. With solvents like acetone and MEK and with MEKP as the catalyst, this stuff is not to be trifled with. Besides, it stinks to high heaven until it’s cured. I still recommend waterborne finishes, particularly KTM-9, to small-production and hobbyist luthiers and anyone unwilling or unable to make this kind of investment in finishing equipment. ◆
