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Cleaning Shop, Part 2

Cleaning Shop, Part 2

by John Calkin

see also,
Cleaning Shop Part 1 by John Calkin

 

There aren’t many scraps in a guitar shop that are useful for making guitars. What guitarmaker would throw those out? But if you scale down to flat-back mandolins or ukuleles you can make use of a lot of expensive material that would otherwise end up in a landfill. The wood I threw out in Cleaning Shop Part 1 was wood I thought I wouldn’t live long enough to use. I had no one to pass it on to. After working for Huss & Dalton for 19 years and more than 4000 guitars I had a crazy amount of scraps. The material I still have should keep me working on my own for years to come.

Quartersawn spruce and cedar strips for center seam back grafts. All photos by John Calkin.
Fingerboard cut-offs for banjo tailpieces, heel caps, inlays, etc.
Rosewood aplenty for headstock caps, inlays, heel caps, laminated fingerboards and bridges.
Material for back grafts and end grafts.
Neck stock. (The fingerboards didn’t come from anyone’s scrap pile.)
Spruce and mahogany ukulele tops and backs. Mahogany for uke sides comes from the neck stock.
More fingerboard cut-offs, good for fingerboard bindings and laminated bridges.
Just to present ideas, these ukulele or mandolin fretboards were laminated from mahogany and rosewood.
A banjo tailpiece.
Unfinished boxes made of mahogany, rosewood, and ebony. What? You don’t make crafty gifts and stuff in your shop?

see also,
Cleaning Shop Part 1 by John Calkin

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Violin Setups, Part One

Violin Setups, Part One

by Michael Darnton

from his 1990 GAL Convention lecture

Originally published in American Lutherie #35, 1993 and Big Red Book of American Lutherie Volume Three, 2004

See also,
Violin Setups, Part Two by Michael Darnton



Setups represent one of the most important aspects of violin work. They are the most changeable part of a violin and can make the difference between a customer liking or hating a violin. People who do setups for a living in large shops do a lot of them — countless numbers of bridges, pegs, posts, and nuts. If you’re making one or two or twenty instruments a year you’re not going to be doing many setups. For the people who do those things everyday, it’s a very specialized art and they have very rigorous standards. With that in mind I’m going to try to communicate to you some of those standards, along with some actual “how-to” hints.

Tools

A bench hook (Photo 1) is simply a piece of wood that has a strip nailed to the bottom on one end and a strip nailed to the top on the other end. It hooks over the front edge of the bench and gives a stop to work against. On the under side of my bench hook I’ve glued a piece of sandpaper (Photo 2). If a tiny, thin piece of wood needs to be planed thinner, I flip over the bench hook and use the sandpaper as a traction area.

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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.

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Violin Setups, Part Two

Violin Setups, Part Two

by Michael Darnton

from his 1990 GAL Convention lecture

Originally published in American Lutherie #37, 1994 and Big Red Book of American Lutherie Volume Three, 2004

See also,
Violin Setups, Part One by Michael Darnton



Bridge

When fitting a bridge, the first thing to determine is the proper placement. Ideally the bridge is exactly centered between the inner nicks on the f-holes. This assumes that the holes are centrally located on the violin, which is not always the case, and that the fingerboard is pointed at that position, which it commonly isn’t. The most important aspect of bridge placement is that the string path should be in a straight line. That is, the bridge should be directly between the nut and the end button. In this centering I would expect a maximum total deviation of about .5MM, and I would try to compromise this adjustment the least, assuming that the strings remained pretty much over the center of the fingerboard. If the neck was pointed really wrong I might consider resetting it. Also, I always check to be sure of the position of the end button, and I’ll move it if necessary. In some instances this can be an easy method of correcting for a slightly-wrong neck set. If the f-holes were really off center on an old instrument and I had the time and money, I’d consider resetting the neck and end button off center to match, possibly replacing the neck so that the heel would still point (although crookedly) at the button at the top of the back, minimizing changes to the button.

Anyway, with an understanding of the problem and the possibilities, find a good place for the bridge to sit in the “east-west” dimension, then determine the proper “north-south” location. Ideally, the length of the neck from the nut to the edge of the top next to the neck on the E-string side should be 130MM, and from that point to the middle of the bridge 195MM; a ratio of 2:3. Consistency in this ratio keeps the positions of the player’s fingers relatively the same compared to the edge of the body, no matter what the total string length — an important factor in finding notes in the upper positions. If the length on the neck is off, the position of the bridge should be altered to compensate. For instance, if the neck length is 128MM, the distance to the bridge (the “stop”) would be (128/2)×3=192MM. This is the theory, at least, but I should also warn you that like most things in the violin world this is a subject of controversy, because some people believe that the total length of the string is the most important thing and would deal with the 128MM neck by making the stop 197MM instead. These people maintain two things. Firstly, that the player will quickly adjust to the new ratio. This is true — just ask a viola player. Violas are notoriously nonstandard. Secondly, they assert that the proper string length is important for the tone of the instrument. This is possibly but not necessarily true. Now you know the logic; the decision is yours.

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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.

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Violin Setups, Part Two

by Michael Darnton

from his 1990 GAL Convention lecture

Originally published in American Lutherie #37, 1994 and Big Red Book of American Lutherie Volume Three, 2004

See also,
Violin Setups, Part One by Michael Darnton



Bridge

When fitting a bridge, the first thing to determine is the proper placement. Ideally the bridge is exactly centered between the inner nicks on the f-holes. This assumes that the holes are centrally located on the violin, which is not always the case, and that the fingerboard is pointed at that position, which it commonly isn’t. The most important aspect of bridge placement is that the string path should be in a straight line. That is, the bridge should be directly between the nut and the end button. In this centering I would expect a maximum total deviation of about .5MM, and I would try to compromise this adjustment the least, assuming that the strings remained pretty much over the center of the fingerboard. If the neck was pointed really wrong I might consider resetting it. Also, I always check to be sure of the position of the end button, and I’ll move it if necessary. In some instances this can be an easy method of correcting for a slightly-wrong neck set. If the f-holes were really off center on an old instrument and I had the time and money, I’d consider resetting the neck and end button off center to match, possibly replacing the neck so that the heel would still point (although crookedly) at the button at the top of the back, minimizing changes to the button.

Anyway, with an understanding of the problem and the possibilities, find a good place for the bridge to sit in the “east-west” dimension, then determine the proper “north-south” location. Ideally, the length of the neck from the nut to the edge of the top next to the neck on the E-string side should be 130MM, and from that point to the middle of the bridge 195MM; a ratio of 2:3. Consistency in this ratio keeps the positions of the player’s fingers relatively the same compared to the edge of the body, no matter what the total string length — an important factor in finding notes in the upper positions. If the length on the neck is off, the position of the bridge should be altered to compensate. For instance, if the neck length is 128MM, the distance to the bridge (the “stop”) would be (128/2)×3=192MM. This is the theory, at least, but I should also warn you that like most things in the violin world this is a subject of controversy, because some people believe that the total length of the string is the most important thing and would deal with the 128MM neck by making the stop 197MM instead. These people maintain two things. Firstly, that the player will quickly adjust to the new ratio. This is true — just ask a viola player. Violas are notoriously nonstandard. Secondly, they assert that the proper string length is important for the tone of the instrument. This is possibly but not necessarily true. Now you know the logic; the decision is yours.

The third measurement to think about at this point is the final height of the bridge. Usually the top of the fingerboard projected to the position of the bridge should fall about 27MM over the center of the top. I check this measurement with a stiff 30CM rule on the board and another 15CM rule to make the measurement. On old violins that haven’t been well cared for, this will often be 25MM or less, and that situation needs to be taken care of before the bridge is cut by resetting the neck, “pulling up” the neck (a repair beyond the scope of this discussion), or fitting a new or a “therapeutic” fingerboard, depending on the situation.

There are many different kinds of bridge blanks available, especially different models from German suppliers, but the standard with which all others are compared is the Aubert “Deluxe” (Photo 31). It’s marked by the word “AUBERT” in an oval with “DE LUXE” printed over it. This is quite an expensive bridge, and not necessary for any but the best violins, that is, ones valued in tens of thousands of dollars. Aubert makes several much less expensive models that can serve just as well. A particularly good bargain is their #7 (same marking, no “DE LUXE,”) which is 95% the quality of the Deluxe at 40% of the cost. The #5 (“Aubert” in block letters, no oval, and “Made in France” under the “Aubert”) costs even less and is fine for most violins. It’s about 70% of the value of the Deluxe for about 20% of the cost. I’m just making these numbers up.

Photo 31. All photos by Michael Darnton.

Any bridge other than an Aubert rates about 40% of the Deluxe or less in quality. Aubert bridges are specially treated, which is supposed to make them better sounding and certainly does make them easier to cut. In my experience the difference in sound is real. Beware of “Aubert model” bridges, which aren’t the real thing, and the “Aubert” bridges with a star brand; they aren’t real either.

Beyond selecting a brand of bridge, there are other things to look for: even grain, perfect quartering on one face (indicated by prominent rays running up the face perpendicular to the grain), grain running straight across the bridge, and good color and texture. Don’t get real bothered about the size of the rays on the face of the bridge. Lots of times when you plane the bridge down to the proper thickness, the angle of the face to the rays changes and the rays go away. It’s the same piece of wood; has it gotten worse? I don’t think so. Sometimes when you thin a blank with shorter rays, it brings the rays out better. Do you charge more?

People have very definite opinions as to which is the front side and which is the back side of the bridge, and it’s all based on those medullary rays in the wood. Many people will tell you that the spotted side (which is usually the side with the stamp on it) belongs towards the tailpiece, the logic being that if those rays are on the back they are running vertically, and they offer the most vertical stiffness through the bridge and a direct conduit from the string to the top.

The other school maintains that if you put the rays facing the fingerboard they offer extra stiffness to the face of the bridge that is vulnerable to warping, which you all know bridges do. I like this argument better, and I also think it’s the way the maker intended the bridge to be positioned: if you put the spots on the front, all the cutouts are oriented straight through the bridge parallel to the underside of the fitted feet. If you turn it around so that all the spots are on the back, then all the cutouts come out about 5° off straight through. That means that in order for the cutouts to go straight through you have to make everything bigger. It forces you to leave more beef at the bottom to twist the bottoms of the feet around to the other direction.

So now I ignore completely which side the spots are on and which side the stamp is on, and I always look which way the cutouts are going through the bridge. I put that side so the cutouts are parallel to the top of the violin, do less cutting, and avoid the whole question as to which way is tonally better. I’m sure this randomization of process will offend many people, but I just haven’t seen any difference in tone either way.

I worked with a maker from France who said he thinks it all has to do with Americans’ materialism. We use the most expensive bridge there is, then carefully position it so that the player can see the well-known stamp and the long spots and know what we’ve done and be happy. There’s a lot of sense to this, especially when you consider that Aubert makes about five cheaper grades of bridge but you never see them here.

You often hear that the back of the bridge is perpendicular to the top (Photo 32). In my experience this really isn’t quite true. If you put a square on the edge in the C bout and sight the side of the bridge against it you’ll usually find that the square comes out the bottom about one-third of the way from the back of the bridge when it’s against the back edge of the top of the bridge. The bridge is tilted back a little but not so much that the back is perpendicular. In most cases if you put a square on the back of the bridge you’ll find that the feet are actually perpendicular to the back of the bridge, though.

Photo 32

The first step in fitting the bridge should be to thin the bottom section. Most bridges are over 5MM thick at the feet. With a small plane, thin the lower half to 4.5MM while holding the bridge in the cupped fingertips of your opened hand. I’ve seen fancy jigs to hold bridges for this, but they really aren’t needed. Since the side of the bridge facing the board will end up rounded with a slightly greater bulge than the tailpiece side, this is the side I remove the extra thickness from after a pass or two on the other side, just to straighten up the area around the feet. More shaping of the faces takes place after the bridge is cut to its final height, so don’t spend any time on the upper half of the bridge at this point.

Carbon paper works well for fitting the feet, with the reservation that there will always be carbon in places where it doesn’t belong, so you have to use your eyes too. It’s better to carve off a bit extra from the bottoms of the feet right at the start in the rough fitting, since there’s usually too much wood there, then do the fitting from that point, so that you won’t have to take much off the tops of the feet when you’re finished to bring them to the proper thickness (1.0MM). This also prevents the cuttings in the bridge from ending up high in the bridge, getting too close to the strings, and weakening the bridge.

I use a large (18MM) knife with a curved edge to fit bridge feet (Photo 33). A smaller one, maybe 15MM, would work as well, but I do like the extra mass of the larger blade for this job. The curved edge permits you to carve out areas in the center of the feet without touching the edges. When done, the feet should fit tightly all around the edge, like the bridge grew in place on the instrument. As in many violin-related subjects there are several opinions about how feet should fit. Traditionally-trained makers believe the whole surface of the feet should touch the top, giving better contact for the transmission of vibration. Some makers believe the center area should be hollowed out quite a bit so that only the edges touch, communicating the forward and backward torque of the bridge more certainly . If you can’t fit feet, this sure makes the job easier. Great (and mostly unsubstantiated, in my opinion) tonal benefits are claimed by each school. Both schools agree that the bridge shouldn’t be resting on a point or two at the center of the feet.

Photo 33

When I fit feet I fit them as well as I can, then scrape out just a bit in the center area so the edges fit firmly. Then when I string up the instrument I bring the strings up tight enough to firmly hold the bridge in place, carefully align the bridge in its proper spot at the right angle, lift one foot at a time and place 220-grit sandpaper under the foot, grit up (Photo 34). Then I hold the bridge in place and pull the paper out sideways about 1/2" — no more. Doing this only once snugs the feet down nicely around the edges but still leaves the center slightly away from contacting the top. It doesn’t take too long for the feet to flatten out under the pressure of the strings, or, in the case of a new instrument, to bury themselves in the varnish down to the top wood.

Photo 34

After the feet have been fit, the height of the strings is established. The easy (but not terrifically accurate) way to do this is to slide a long rule on the fingerboard along the path of the E and G strings until it touches the bridge just below the point where each string passes over the bridge and make marks on the front of the bridge with the end of the rule. Measure up from those points 4.0MM (E string) and 6.0MM (G string) and make two more marks against which to align the template for the arch of the top of the bridge (Photo 35). Position the template on the marks and mark the arch with a marking point. Cut and carefully file the top of the bridge to this scored line. If everything works out right the strings probably will be the proper heights (3.5MM and 5.5MM). To do a better job, leave the arch a bit high, string up the instrument, and file the string grooves until the E and G strings are the right height. Then remove the bridge and use the template and files to finalize the arch based on the locations of the two outer strings.

Photo 35

When the top and the bottom of the bridge are finished, it’s time to work on the middle. At this point the top of the bridge will vary in thickness and should be made a uniform 1.5MM thick. This is done by removing wood from both the front and the back sides; more from the side that will face the fingerboard than from the tailpiece side. Carefully plane the back face towards the corners, thinning them a bit and removing a little more on the E-string side. Look at the bridge from above and try to make the line of the back of the top of the bridge as straight as possible but placed a hair diagonally so that the E string will be just a bit shorter than the G when the bridge is finished.

When the back edge looks good, work on the front side, planing it until the top edge of the bridge is 1.5MM thick from one corner to the other. When planing either face, don’t just remove wood from near the top, but blend the thinning into the body of the bridge all the way down to the waist. Both faces of the bridge should not be flat or they will look and be weak. Leave the surface just a bit puffy, shell shaped. Finish the faces by placing a piece of 150-grit sandpaper, then 220, and 400 on a flat surface and rubbing the bridge on them successively until the bridge is smooth and all facets from the planing are gone. Be careful not to round over the surfaces excessively near their edges.

Now that the functional parts of the bridge are mostly finished, it’s time to worry about the pretty stuff. For this job, a 3MM knife sharpened to a long, sweeping point is ideal (Photo 36). The bevels on this knife should not be flat but rather slightly rounded. If they are too flat, the knife will dig in and chatter rather than follow the tight curves of the feet and kidneys of the bridge. The feet should be trimmed to 1.0MM high, ankles to 3.5MM wide. The outside of the ankles, feet, and outer spurs on the knees are trimmed so the knees mirror the feet and the line between the two is a pure arc of a circle. All the arcs should end with a little kick. Be careful that the very ends of the arcs are not flat, but continue the arc, and the tips of the feet and spurs should all be a little bit thicker than the point just before the tip. The shape of the spurs in the kidneys is trimmed to match the part of the feet beneath them and the kidneys themselves opened up to an attractive shape. Cutting them too high above the bottom of the heart weakens the bridge too much, so don’t get carried away. The arch across the bottom of the bridge is blended into the line of the feet, complementing the bottoms of the feet. (The more pointed the arch of the top, the more rounded the arch between the bridge feet should be.) Bevels are put on the four straight edges of the bridge sides (these bevels are about .7MM wide at the bottom and taper out to nothing at the top edge), and the spurs of the kidneys are beveled back to points from each side. Bee stings are cut in from the spurs on the knees.

Photo 36

The top edge is finished by filing a facet along each edge on the top, and the top edge is then rounded with 400-grit sandpaper leaving sharp edges where the face and top rounding intersect (Fig. 1).

Figure 1. Stages in rounding the bridge top.

The position of each string is marked and a shallow notch filed or even pressed into place. The E and G strings should be 35mm apart, measured over the arch of the top of the bridge, and the other strings equally spaced between (Photo 37). The strings should be centered on the bridge and the fingerboard, or possibly set about .3mm over to the G side, if you wish, to allow for the pull the player’s hand exerts on the strings. A 4.5MM × 9.0MM piece of drum skin can be glued over the top of the bridge under the E string so the string doesn’t cut into the top of the bridge. For an example I’ve included a photo of one of my bridges (Photo 38), but it’s only one style of many possible. As you gain experience, however, you’ll begin to realize that there are such things as good style and bad. My first bridges were, shall we say, individualistic. I hope none of them end up in a museum 300 years from now with my name attached.

The final step, after everything else is right, is to stain the bridge so that it doesn’t look so white. Currently I’m using nussbaum in water applied with an airbrush.

Photo 37
Photo 38

Strings and Tailpiece

I was taught to set up a violin perfectly normally at the start and work from there in adjusting. This is a good idea. It gives you a baseline to work from. For strings this means starting with a normal set — no crazy mixes like a Super-Sensitive G, a gut D, a Dominant A, and a gut E, to state things in extreme terms. Put on a standard string set, then adjust the instrument to give the best sound with that string set. Most classical players I am familiar with prefer a medium-gauge Dominant G, silver D and A, with a Kaplan Golden Spiral E. The Kaplan E is cheaper than the Dominant and gives a fatter, firmer sound. Start changing things one at a time, doing the absolute minimum possible to get the sound right. For instance, moving the post back 10MM might give me the sound that I want (I hope it wouldn’t). I might move it back a millimeter, then I might find something else to play with. For instance, I’d try moving the tailpiece closer or farther from the bridge.

The distance of free string between the tailpiece and the back of the bridge is called “afterlength” (Photo 39). A “normal” setting is usually 55MM–57MM. The shorter the afterlength, the tamer, more refined, more mellow and round the sound will be, but the power and freedom of the instrument can suffer. Pull the tailpiece way back (by shortening the tailgut) and the instrument gets wilder. It gets brighter and wolfier and harder to manage. This rule doesn’t hold every time, however, so it’s always worth moving the tailpiece back and forth just to see what the effect will be.

Photo 39

Usually tailpieces are so long that the afterlength can’t even be set to 55MM. In order to pull the tailpiece even that far back you have to saw some off the small end, at the same angle as the original end, which you then file smooth and bevel to break the sharp edge.

Another tailpiece issue is fine tuners (Photo 40). In one shop where I worked we called the traditional fiddler setup with four big, heavy fine tuners the “heavy-metal setup.” That’s descriptive of the weight rather than the tone because that kind of stuff on the tailpiece strangles the instrument. If the pegs don’t work right (of course you really should be able to make them work right) or your customer never learned to tune a violin, at least try to find an Akusticus tailpiece. It’s made of plastic, has four tuners built in, and is closer to the right weight than the Tomastik tailpiece that’s made entirely out of metal. The best single tuner is the Hill-style fine tuner which fits up in the little keyhole on the tailpiece that the string comes out of. It has a little finger behind the saddle in the tailpiece and doesn’t change the afterlength of the E string at all. I always file the edges off where the string rests on the little hook. The stamping process that forms the hook always leaves a burr which usually causes E strings to break there, in my experience. With some thin tailpieces it may also be necessary to use a flat needle file to remove a bit of the body of the hook so that it doesn’t bump the tuner’s retaining nut, preventing full movement of the hook.

Photo 40

Saddle

It’s not often that something needs to be done to the saddle, but if the saddle is unusual it might be good to ponder why. A normal saddle is about 6MM–7MM high (Photo 41). A higher or lower saddle is used with higher or lower than normal arching in order to maintain the string angle within normal limits. If the pitch of the neck is low (resulting in a low bridge) a high saddle will lessen the string pressure on the top even more and may be detrimental to the tone. On the other hand, an instrument with a high pitch and bridge may benefit from having a high saddle. Sometimes just cutting a saddle down a bit can have a positive effect on the instrument’s tone and may be a minimally invasive (and cheap) effort to compensate for a low neck pitch, compared to a new neck set.

Photo 41

End Button

There’s not much to be said about the end button. It should be in the center of the instrument, as should all the other elements of the string path that I’ve been speaking about.

I use a machinist’s surface gauge to determine the centering of the end button and the neck. The violin is placed on its edge on a flat (really flat) surface and the gauge scriber is set to graze (or point at) the object being measured. The violin is flipped to the other edge and the scriber is aligned with the same point. The point does not have to be on the centerline if the object is symmetrical and centered. In (Photos 42 and 43) I’m working on the edge of an end button and the edge of the fingerboard at the nut. The distance the scriber is misplaced on the second checkpoint is twice the centering error, so if the scriber were 1.0mm from the end button on the second check, the button would be .5mm off center. This works only if the instrument (or the top, specifically) is perpendicular to the base surface and the edge is unworn. There are several ways to compensate for problems with the edge and twists in the instrument. I’ll let you invent your own.

Photo 42
Photo 43

The end button should be leaning backwards a bit against the tension of the strings. If it isn’t, all of the pull of the strings will be supported by the ring next to the ribs, which will eventually break. In a virgin instrument this piece is usually turned to the middle hole of the peg shaper (the same hole that viola pegs are turned to), but in older instruments it may be necessary to make it larger or to bush the hole and redrill it to a more normal size. This may also be necessary if the end button is out of line with the string path.

There’s much more to know about setup than what has been covered here. Two other important topics are bass bars and neck sets. Of course there’s the whole subject of adjustment, too, which has just barely been mentioned. I hope some of this will be helpful to you in your day-to-day work and get you started thinking about some of the many problems involved in setting up instruments of the violin family.

See also,
Violin Setups, Part One by Michael Darnton

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Business Ethics in Lutherie

Business Ethics in Lutherie

by Lawrence Lundy

Originally published in Guild of American Luthiers Quarterly, Volume 6 ,#2, 1978



Among the purposes listed in the G.A.L.’s charter is to encourage among luthiers the highest possible standards of ethical business practices in the operation of their enterprises. The questionnaire sent out at the end of last year was intended to acquire a range of ideas on the subject of current business practices as they relate to the customer. The response was surprisingly good with over 90 members responding to the joint questionnaires.

In writing this report, I have tried not to set any standards by suggesting what the average policy is, or the one followed most frequently, or by inserting any of my own values. The idea was to make a shopping list by including every idea mentioned by respondents for modifying their own practices. Because such reporting lacks personality (both mine and those of the respondents) and tends, therefore, to be inherently dull, I have also tried to be as brief as possible.

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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.

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Mossman Truss Rod Adjustment

Mossman Truss Rod Adjustment

by S.L. Mossman

Originally published as Guild of American Luthier's Data Sheet #263, 1983



Explanation of the Truss Rod and how it Works

The steel rod is laid in at a curve. The curve extends from the first fret and tapers off at the ninth fret. Since the rod is anchored at both ends, when the nut end is tightened it simply shortens the rod by pulling the curve out of the rod and straightening itself, forcing the low part of the rod up and pulling the hight point down, which is the point of least resistance, causing a back bow in the neck.

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.