Posted on August 11, 2021May 21, 2025 by Dale Phillips Frets and Fingerboard Care Frets and Fingerboard Care by Randy Stockwell Originally published in Guild of American Luthiers Quarterly Volume 7, #2, 1979 and Lutherie Woods and Steel String Guitars, 1998 Neck Shapes. I credit Leo Bidne for his perceptions of the relationship between the fingerboard bow and the string’s motion. I use heat treatment to obtain these results when the problems are severe enough. But I find that most instruments, while needing some neck curve help, are not in serious enough trouble to merit the use of heat. Most can be put in the proper curvature through careful and diligent fret dressing and tension rod adjustment (granted sufficient fret height to begin with). When the frets are too low or the curve too great, refretting is usually called for anyway. The fingerboard itself can then be reshaped to the suitable curves. Of course, if the fault is bad enough to call for a major removal of wood, I definitely resort to heat, neck resets, major neck rebuilding, and so on. Even after heat treatment, I find it necessary to finish with fingerboard and/or fret-dressing procedures. Become A Member to Continue Reading This Article This article is part of our premium web content offered to Guild members. To view this and other web articles, join the Guild of American Luthiers. Members also receive 4 annual issues of American Lutherie and get discounts on products. For details, visit the membership page. If you are already a member, login for access or contact us to setup your account.
Posted on August 11, 2021May 16, 2025 by Dale Phillips Applications of the Silicone Heating Blanket in Violin Making Applications of the Silicone Heating Blanket in Violin Making by George Borun Originally published in American Lutherie #34, 1993 and Big Red Book of American Lutherie Volume Three, 2004 In American Lutherie #25, Mike Keller describes how he uses silicone heating blankets for bending guitar sides, and mentions an earlier article in Fine Woodworking. The potential of these devices for use in violin making became obvious to me, and with some experimentation and adaptation, I’ve developed specific applications for the violin maker. Silicone heater blankets, also called flexible heaters, are available from two sources, with a number of standard sizes in stock at each company: Watlow Electric of St. Louis, Missouri (www.watlow.com) and Benchmark Thermal of Grass Valley, California (www.benchmarkthermal.com). Watlow markets through distributors. They have a large selection of stock sizes up to 35" long. Benchmark has a smaller stock size selection, but their prices are considerably lower. They will make any size you wish, but that adds to the cost and delivery time. Stock maximum length is 20", but this is more than long enough for violins. In bending bass ribs, I use two 10" wide blankets for the longer pieces, and only one for the center bout. The best units are 4W/sq.", rather than the 2W models. This type will get up to 500°F in a couple of minutes. Product catalogs are available which list the various sizes. Become A Member to Continue Reading This Article This article is part of our premium web content offered to Guild members. To view this and other web articles, join the Guild of American Luthiers. Members also receive 4 annual issues of American Lutherie and get discounts on products. For details, visit the membership page. If you are already a member, login for access or contact us to setup your account.
Posted on June 1, 2021May 21, 2025 by Dale Phillips Blackboard Eraser Polisher Blackboard Eraser Polisher by Michael Dresdner Originally published in Guild of American Luthiers Data Sheet #288, 1984 and Lutherie Woods and Steel String Guitars, 1998 I’ve been using a blackboard eraser to do final dressing on my frets. I take this nice soft eraser and a piece of 600 paper and go across the fretboard. It’s beautiful; it just follows the curve and gives you a nice even rounded top. This is for polishing, after you’ve shaped the frets with files. ◆
Posted on May 6, 2021May 19, 2025 by Dale Phillips Tuning the Guitar Tuning the Guitar by Ian Noyce Originally published Guild of American Luthiers Data Sheet #56, 1977 and Big Red Book of American Lutherie Volume One, 2000 Because the guitar has fixed frets set to an even temperament, tuning it properly is not the cut-and-dried process that many people believe. And due to various factors that we’ll get to shortly, if the guitar’s bridge is placed exactly where the nominal scale length says it should be, the instrument may not play in tune at all. The two most common methods of tuning are: (1) the 4th- and 5th-fret method and (2) the harmonic method. Both of these methods are often misunderstood through confusion regarding perfect (or Pythagorean) intervals and even-tempered intervals. The 4th- and 5th-fret method. Theoretically, this is the simplest method as it simply involves tuning unison intervals. The A string can be tuned to an A tuning fork, then the bass E is fretted at the 5th fret and tuned in unison with the open A. The D string is tuned in unison with the 5th fret of the A, the G string is tuned to the 5th fret of the D, the B string is tuned to the fourth fret of the G, and the high E is tuned to the 5th fret of the B. In practice this can be difficult because any errors are cumulative. It’s also true that many guitars tuned this way will not play in tune in all keys. Become A Member to Continue Reading This Article This article is part of our premium web content offered to Guild members. To view this and other web articles, join the Guild of American Luthiers. Members also receive 4 annual issues of American Lutherie and get discounts on products. For details, visit the membership page. If you are already a member, login for access or contact us to setup your account.
Posted on May 5, 2021May 22, 2025 by Dale Phillips Rule of 18 vs Rule of 17.817 Rule of 18 vs Rule of 17.817 by James Buckland Published online by Guild of American Luthiers, May 2021 At the 2014 GAL Convention, I conducted a lecture/presentation entitled “Mythbusting the Rule of 18”. The intent was to explore, and possibly refute, some of the misconceptions concerning the Rule of 18. As conventional wisdom goes, the old rule of 18 was, at best, an approximation on how to calculate fret positions. In truth, it is a better formula than it’s generally given credit. Unlike many historical predecessors, such as Juan Bermudo’s approaches using Pythagorean ratios, the Rule of 18 is based on the concept of equal temperament, probably before the term existed in the vernacular. But, most importantly, Rule of 18 includes its own compensation factor in regard to the position of the bridge. Most commonly used today, is the square root of two, or 17.817, as the factor with which to divide string length. The result is believed by many to be more accurate based on the fact that it places the 12th fret at the exact midpoint of the vibrating string length. Since we all know that the 12th fret is the octave above the open string, it makes common sense that it should be in the exact middle of the vibrating string length. However, it is also well known that a guitar built this way will play out of tune, with intonation problems increasing the further one plays up the neck. The solution is to compensate by increasing the string length slightly, generally by moving the bridge position. But, by how much? Examine enough classical guitars fretted with a “650MM scale”, and you’ll find the actual vibrating string length is generally longer, by 2 to 4MM. There doesn’t seem to be much more than vague empirical evidence in just how much to use. In other words, a little bit of “Kentucky Windage” is considered good enough. (For you non-shooters, Kentucky Windage is the practice of adjusting your aim to compensate for wind, without the use of any mechanical features on the weapon.) To me, this is a seemingly strange attitude considering the derision generally cast upon the good old Rule of 18. Maybe “17.817” just sounds more precise than saying “18”? So, here’s a practical example of the similarity between the two approaches when bridge compensation is taken into account. I began by calculating a fret scale for a 565MM string length (as might be used for the terz guitar in GAL Instrument Plan 80) using the “Rule of 18”. The results are shown in Table 1. Then, I took the resulting value for the distance between the nut and 12th fret (280.446MM) and multiplied it by two. Next, the resulting value (560.892MM) was used to calculate a fret scale using the contemporary 17.817 factor. The calculations are shown in Table 2. Table 1 Table 2 Notice the outcome! Although the vibrating string lengths are different (560.892MM vs 565MM) the results for the fret placements are generally from about a tenth of a millimeter at the first fret, approaching one millimeter towards the higher frets. To put that into context, consider real world variabilities typically introduced during fretboard fabrication, from layout, to slot cutting, to fret dressing and crowning. Or, compare this to the guesstimate made by many luthiers when choosing bridge placement compensation. But, what about the issue of the difference in string lengths? Well, as stated above, most luthiers know that to satisfactorily use the 17.817 approach, one must add their own bridge compensation (hence the “Kentucky Windage” analogy). So, if you add 2-4MM bridge compensation to the 560.892MM string length, you can see that resulting vibrating string length gets pretty close to 565MM! But, there is another way of looking at the data that shows even more surprising results. The tables of values reflect the string length from the nut to the respective fret(s). What about the other length of the string, the vibrating string length from the fret to the bridge, the part of the string we actually hear? The greatest discrepancy between the two tables is found with the 24th fret. In the case of the Rule of 18, the distance from the 24th fret to the bridge is 143.312MM. In the case of the 17.817 factor, the distance is 140.221MM. Add 2MM compensation, and the value increases to 142.221MM. Add 3MM compensation, and the value increases to 143.221MM. Add 4MM compensation, and the value increases to 144.221MM. In other words, the discrepancy between fret placement values calculated with either the Rule of 18 or the Rule of 17.817 is less than the variables introduced through the subjective choice of bridge compensation which must be made when using the latter rule. When comparing the other fret values, the difference between the two table of calculations is even less. Does the use of the Rule of 18 vs 17.817 result in a significantly discernible difference, given other contributing factors? Maybe the old guys knew more than they’ve been given credit? ◆ Thanks to Nitin Arora for writing the fret calculating program “Eighteen Rules” found on his website. At the 2014 GAL Convention, author James Buckland also demonstrated the use of proportional dividers for marking fret positions. Set the big end of the dividers to the scale length. The little end now shows you the distance from the nut to the first fret. Re-set the long end to the distance form the first fret to the bridge. You are off and running. Ron Fernandez tries it. All photos by Tom Harper.
