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Improved X Bracing

Improved X Bracing

by Don Musser

Originally published as Guild of American Luthiers Data Sheet #172, 1981 and in Lutherie Woods and Steel String Guitars, 1997



After building a number of guitars with the standard steel string X-bracing pattern, I noticed some problems. First, even when the braces were precurved to a 25' radius, there was still a deformation just behind the bridge that was caused by the upward pull of the strings on the inner bridge plate. Energy which could have gone to sound production in the whole top was being lost to wood deformation in a small area of the top.

Second, there was always a problem of creating a guitar having both an outstanding bass and treble response. Good bass response requires less or lighter bracing on the bass side of the top. A crisp, well-defined treble requires more or slightly heavier bracing on the treble side. The challenge was to be able to achieve both without retarding either.

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In Search of the Perfect Cone

In Search of the Perfect Cone

by Tim Earls

Originally published in American Lutherie #30, 1991 and Big Red Book of American Lutherie Volume Three, 2004



I think I've got it. I have here an untested method of finding the exact, correct multiple radius for any given fingerboard using simple barnyard geometry and no computer. Danny Rauen and Tim Olsen wrote interesting articles on multiradiused, or conical, fretboards in American Lutherie #8. (See Big Red Book of American Lutherie Volume One, p. 298.) Great stuff! Let’s talk about cones for a moment.

A cone is a tapered cylinder extended up to a point. Or a tapered cylinder is a cone with its point lopped off, take your pick. You knew that. Bear with me. In a two-dimensional view, this looks like Fig. 1. The circular base of the cone is seen as a horizontal line, since you’re looking at its edge. The height of the cone, what I call “true length” is measured on the centerline from base to point. The side line of the cone I call “true distance.” The radius at any spot on this cone can be found by drawing a horizontal line from the centerline to the true distance line and measuring it. You probably knew that too.

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Skin Heading Ethnic Drums, Etc.

Skin Heading Ethnic Drums, Etc.

by Topher Gayle

Originally published in American Lutherie #2, 1985



Derbeckis (A.K.A. dumbegs or Arabic tabla) are medium-sized (10" to 18") hand drums used most frequently in Middle-Eastern folk and Belly-Dance music, and also heard in jazz idioms. Two main types of the drum exist: metal bodied drums, usually Turkish, utilizing a mechanical drumhead tensioner much like that on bongos or conga (which drummers frequently want to have replaced by banjo tensioners); and the clay-bodied drums which come in a large variety of sizes and shapes. Wood-bodied drums also exist and may usually be treated as clay (for the most part).

Tim Olsen asked if various skin-headed stringed instruments might be treated by this device. I have not done so myself, but I don’t see any serious complications. A radiator hose clamp chain can be used to fix the skin to the side of the body if the body side joins the top at a right angle. I used this technique on a small wooden drum with good results. Blocks were required to raise the body up to the top frame hex, since the drum was so short. The skin was brought up to tension as described below, and then the radiator clamps attached. The assembly was let dry just as is usually done.

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One Way to Make Kerfed Lining

One Way to Make Kerfed Lining

by Richard Ennis

Originally published in American Lutherie #2, 1985



In general, linings exist in three or four types, all of which are related to one another. There is the solid type which must be bent before use; individual blocks, which might be thought of as the solid type of lining cut up to a more manageable size; laminated linings, another variation of the solid type; and kerfed linings. The kerfed lining is perhaps best seen as either a line of individual blocks linked together, or as a solid lining kerfed for flexibility.

Here is how I make kerfed linings. It is a method with very little wastage and is efficient for use in a small workshop. When using the approximate dimensions given below it produces a lining that appears as a series of individual blocks linked together on a wooden ribbon.

I select my timber for linings by giving first consideration to the working properties. I want to avoid ragged edges from the numerous saw cuts, but look for wood with good gluing capability, that sands well, and that is not too fractious and inclined to split. Willow, alder, and linden are all good candidates, as is tulip tree wood, sometimes marketed as “yellow poplar”.

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White, Yellow, and Hide Glues

White, Yellow, and Hide Glues

by Lawrence D. Brown

Originally published as Guild of American Luthiers Data Sheet #174, 1981 and Big Red Book of American Lutherie Volume One, 2000



This article originally appeared in the FoMRHI Quarterly No. 18, and appears here (revised and expanded) with the kind permission of that organization.

Ultimately, the quality of a musical instrument depends not only on the sweetness of its tone but also on its continued service and durability in a variety of climates. Deterioration of an instrument may occur from internal or external forces. External forces are those that come from hard use or from string tension. Internal forces are the result of the natural tendency of all woods to shrink, warp, and shift position in response to changes in moisture content. Poorly shaped parts that have been forced together by clamping pressure are also capable of generating internal forces by the steady pull on the joint caused by the misalignment.

The structural integrity of the instrument, its ability to stay together and retain an attractive appearance over a number of years, depends on four things: the choice of carefully sawn woods with a uniform, low moisture content; the type and design of the joints used; the experience and expertise of the builder; and the adhesive used in construction. The concern here is glue, although some discussion of closely related factors such as joint design and humidity is unavoidable.

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