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Having established, to my own satisfaction at least, that it would be asking for trouble to make a steel string guitar without a truss rod, the next question was which type to use and whether to arrange to get access to it at the top of the neck or the heel.

My friend Peter Barton, who makes beautiful steel string guitars in Yorkshire, recommended the Hotrod, which is a 2 way adjustable truss rod available from Stewart-MacDonald and looks like this.

But there were a couple of reasons why I had misgivings about this device. One was that it weighs over 100g and I thought it might make a small or medium sized instrument too heavy in the neck. The other was that it’s 11 mm deep and, although it would be easy to rout a deep enough slot to accommodate it, there wouldn’t be room to glue a fillet over it. The top of the slot would have to be covered by the bottom of the fingerboard and I worried that, when the rod was tightened up it might split the fingerboard or cause a bump.

To check, I made a model guitar neck out of a scrap of softwood, routed out a slot, installed the hotrod, glued on a pine ‘fingerboard’ and tightened up the trussrod as hard as I could.

It worked fine. My anxieties were unfounded: no splits or bulges in the fingerboard, even though it was made of nothing more substantial than cheap pine, and I could put a curve in the neck in either direction.

Still, there’s no getting away from that fact that it’s heavy.

An alternative, which is less than half the weight of a hotrod, is a simple tension rod. This what’s recommended by Jonathan Kinkead in his book Build your own Acoustic Guitar (ISBN 0-634-05463-5), where he gives instructions how to make and install it. I liked this idea because of its simplicity and light weight, and because it’s easy to arrange to adjust it through the soundhole, which means that there’s no need to excavate the headstock to provide access to the nut.

If you go for this solution, you have to find a way to anchor the rod at the top of the neck. Kinkead recommends a metal dowel tapped to receive the threaded end of the rod. I made one out of silver steel and repeated the earlier experiment.

It’s easy to install, although it’s important to judge the depth of the hole for the dowel accurately to avoid drilling right through the neck.

And it seemed to work OK too, although obviously it’s only able to bend the neck in one direction. However, when I took the fingerboard off, this is what I saw.

The fixing at the top end of the neck had been pulled out of its cavity and had begun to travel down the neck. Of course, this experimental neck is made of softwood and the problem might be less severe in a real mahogany neck. Even so, I thought there had to be a better solution.

It was the shape that was wrong. The cylindrical nut had acted a bit like a wedge. When I made a rectangular shaped nut out of mild steel, it stayed put.

As you can see, the first nut was unnecessarily wide. A narrower version worked just as well.

That’s what I decided to use in this guitar: a tension rod made of 5mm studding, anchored at the top of the neck with a square nut and adjusted through the soundhole. The nut at the top of the neck was silver soldered to the studding to prevent it moving during any adjustments at the lower end. Tension in the rod is controlled by turning a 5mm column hex nut bearing on a substantial washer at its lower end.

This arrangement worked well in the finished instrument and was more than powerful enough to keep the neck straight against the pull of the strings. Next time I make a steel string guitar, I shall be tempted to use 4mm studding instead of 5mm, which would mean even less weight in the neck.

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As you’ll have gathered from my last post, I’ve been making a steel string guitar recently. That’s something I hadn’t done for a long time, and it got me thinking about truss rods. One puzzle is how they got their name. Doesn’t the word truss conjure up something like the Forth bridge or the roof structure of this magnificent medieval tithe barn¹?

Wikipedia says that, used in an engineering context, a truss is a structure comprising one or more triangular units constructed with straight members whose ends are connected at joints referred to as nodes. So it’s surely an exaggeration to call a rod in the neck of a guitar a truss. Still, it’s not seriously misleading and I expect that most readers will think I’m quibbling.

Another puzzle surrounds the purpose they serve. As far as I know, no classical guitar maker finds them necessary. So why is it that steel string guitar makers never build a guitar without one? The straightforward answer is that steel strings exert more tension when tuned up to pitch than nylon strings and that a truss rod is necessary to counteract this extra force.

But I wondered if this explanation really held water. Using information provided by d’Addario, a reasonable estimate of the combined tension of 6 nylon guitar strings is about 40 kgs, while 6 steel strings exert nearly double that at 70kg. A load of 70 kgs certainly sounds a lot – the weight of an adult man – but don’t forget that it’s acting at a mechanical disadvantage when it comes to bending or breaking the neck of a guitar. The pull is only a few degrees away from parallel to the neck’s longitudinal axis and the compressive forces will be substantially greater than the bending forces.

Using simple beam theory, I made some rough calculations to get a sense of how much the string tension of a steel string guitar would bend the neck. These calculations didn’t attempt to take the taper of the neck into account – I simply pretended that the dimensions of the neck at the first fret remained constant all the way along the neck until it joined the body of the guitar – and they ignored the fact that the fingerboard and the neck are of different woods that have different material properties. (More details of the calculation are given at the end of this post in a footnote, if anyone is interested enough to check².)

The answer turned out to be that, tuned up to pitch, string tension would deflect the nut end of the neck about 1.6 mm forwards of its unloaded position. Although this is bound to be an over-estimate (because the calculation neglected the stiffening effect of the fingerboard and the increasing dimensions of the neck as it descends), I was surprised how large the deflection was. And I wondered if I’d got something seriously wrong. To check, I made a primitive model of a guitar neck to make some actual measurements. As you can see in the photographs below, the experimental neck is smaller in cross section than a real neck but it’s modelled realistically with an angled headstock and nut. Loaded with a 14lb weight, I measured a deflection of 1.47 mm at the nut, which compared fairly well with a theoretical value of 1.26mm derived using the dimensions of the model neck. So I’m moderately confident that my calculations for a real guitar neck aren’t too far out.

It looks as if the obvious answer is at least partly right. You almost certainly do need a truss rod to counteract the bending effect of string tension on the neck of a steel string guitar.

I suspect there’s another reason for truss rods too, and that is to prevent creep. Wood that bears a constant load for a long period tends to deform gradually even when the load is far short of its breaking strain. This is the reason why the ridges of old roofs tend to sag in the middle. In his book, Structures, J E Gordon explains that it’s also the reason why the Ancient Greeks took the wheels off their chariots at night. The wheels were lightly built with only 4 spokes and a thin wooden rim. If left standing still for too long, the wheels became elliptical in shape.

So perhaps I’ve ended up proving something that most guitar makers knew already. However, I don’t feel that the exercise has been a complete waste of time. Musical instruments shouldn’t contain anything that isn’t either necessary or beautiful. Since truss rods certainly don’t fit into the latter category, it’s good to know that they qualify for the former.

Footnotes

1. Thanks to Kirsty Hall for the image of the tithe barn.

2. Details of calculation of neck deflection.

Neck: width = 44mm; depth = 21.5mm; length (to 14th fret) = 355mm
Force exerted by string tension = 700 N
Nut taken as being 8mm above centroid of neck
To work out the area moment of inertia, I assumed that the neck was semi-elliptical in cross section and that the neutral axis ran through the centroid.
Modulus of elasticity of the neck was taken as 10,000 MPa.
Deflection was calculated as Ml²/2EI, where M = moment exerted by strings at the nut, l = length of neck to neck/body join, E = modulus of elasticity of material of neck (taken as 10,000 Mpa) and I = area moment of inertia of neck (assumed to be a half ellipse).

Here are a few photographs of a recently completed steel string guitar. It’s based on a Martin ‘OO’ model but I’ve added, although that’s surely the wrong word, a venetian cutaway. The soundboard is Sitka spruce and the back and ribs are English walnut. I used holly for the bindings and tail stripe, and Rio rosewood for the bridge.





My friend, Dave Crispin, came to the workshop to try it out a few days ago and while he was playing I captured a few moments on an Edirol recorder.



James Gordon, an engineer, materials scientist and naval architect, wrote two books that I highly recommend. I was about to write …to woodworkers but, actually, I highly recommend them to anyone who has the slightest interest in buildings, ships, aeroplanes or other artefacts of the ancient and modern world. My copies have been read and consulted so often that they’re falling apart. They are The New Science of Strong Materials or Why you don’t fall through the floor (first published in 1968, but still in print: ISBN-13: 978-0140135978) and Structures or Why things don’t fall down (first published in 1978 and also still in print: ISBN-13: 978-0140136289). Both are written for a non-expert readership and there’s very little algebra or mathematics. They’re fun too: Gordon writes clearly, wears his learning lightly and the text is spiced by his whimsical sense of humour.

The New Science of Strong Materials has many interesting things to say about the properties of wood and why it’s such a wonderful and versatile material. There’s stuff about how wood is able to cope with stress concentrations and limit crack propagation, about how glues work, the distribution of stress in a glued joint, and many other things of deep background interest, if not of immediate practical significance, to people who use timber.

The second book, Structures, is equally gripping. It explains how medieval masons got gothic cathedrals to stay standing, why blackbirds find it as much of a struggle to pull short worms out of a lawn as long ones, and the reason that eggs are easier to break from the inside than the outside. Of more direct relevance to woodworkers is its straightforward account of how beams work – which means that, if you’re thinking of making something like a bed or a bookcase, you can calculate whether the dimensions of the boards that you’re planning to use are up to the load they will have to bear, which is obviously useful in making sure that your structure is strong and stiff enough.

Slightly less obviously, it’s also helpful in giving you the confidence to pare down the amount of material that you might otherwise have used. A common fault of amateur woodworkers, it seems to me, is that when designing and making something small, they tend to use wood that is far thicker than it needs to be, which means that the finished object looks heavy and clumsy. Conversely, when making something large, they tend to use wood that is less thick than it should be, and the structure often ends up rickety and unstable.

Knowing a bit about beams might also be advantageous for guitar and violin makers. Here’s an example: take a strut or harmonic bar, rectangular in section, that you’re intending to glue onto the soundboard of a guitar. How is its stiffness related to its shape and its dimensions? What’s the best way to maximise stiffness while minimising weight?

Elementary beam theory tells us that, for a given length, stiffness is proportional to the width of the beam and to the cube of its depth. So if you double the width, the stiffness also doubles. On the other hand, doubling the depth, increases stiffness 8 times. If stiffness is what you’re after, it’s a lot more efficient to make the bar deeper than it is to make it wider.

This cubic relation between depth and stiffness could be something worth keeping in mind when planing down soundboard braces after they’ve been glued. If a brace is, say, 6 mm high to start with, planing it down by 1.5 mm to a height of 4.5mm will reduce its stiffness to less than a half of what it was originally. And shaping the braces to make them triangular or arched in cross section also reduces their stiffness considerably.

Mind you, like so many attempts to understand guitars from a scientific point of view, things rapidly get complicated. A structural engineer with whom I discussed the matter agreed with what I’ve just said about the depth of the beam being a powerful determinant of its stiffness. But he pointed out that where a beam is an integral part of a structure, the stiffening effect is much greater than you would guess from calculations that assume the beam is simply supported at its ends. This is certainly the case of guitars, where the braces are glued to the soundboard along their entire length and clearly count as an integral part of the soundboard structure. In such circumstances, he explained, the overall stiffening effect provided by multiple braces will be large and might well overwhelm the influence of the stiffness of any individual brace.

I thought that this was a very interesting idea and that it might begin to explain why so many different bracing systems work remarkably well. In Roy Courtnall’s book, Making Master Guitars, he give plans of soundboard strutting taken from guitars by a number of famous makers. Superficially they’re fairly similar, all being based on a fan-like pattern of 5, 7 or 9 struts. There are minor variations, of course. Some are slightly asymmetrical, some have bridge plates and closing bars and so on. But the  biggest differences lie in the dimensions of the braces. Courtnall shows a soundboard by Ignacio Fleta that has 9 fan struts and 2 closing bars which are 6mm in depth and an upper diagonal bar 15mm depth. By contrast, a soundboard of similar size by Santos Hernández has only 7 fan struts 3.5mm in depth and triangular in section. Applying simple beam theory would lead one to guess that Fleta’s bracing would add more than 10 times the stiffness that Hernández’s does. But perhaps that’s a misleading way to look at it. If one were able to measure or calculate the stiffness of the whole structure, by which I mean the soundboard with its bracing when attached to the ribs, the difference in stiffness between them might turn out to be much less.

It’s a question that might be tackled by finite element analysis and I’d be glad to hear from anyone who has tried. Some work along these lines has been done on modelling a steel string guitar, which at least shows that the approach is feasible.

In the meantime, without a proper theory, we’re stuck with the primitive method of trial and error. Below are some of the bracing patterns that I’ve experimented with. All produced decent sounding instruments but I’d be at a loss if I were asked which particular tonal characteristics were produced by each of the different patterns. It may be that William Cumpiano was right when he wrote (in his book, Guitarmaking, Tradition and Technology):

Specific elements of brace design, in and of themselves, are not all that important. One has only to look at the myriad designs employed on great guitars to recognise that there is no design secret that will unlock the door to world-class consistency.

All this means that I’ve been arguing in a circle. Perhaps the conclusion is that beam theory isn’t very useful to guitar makers after all. Still, if you take up the recommendation to get hold of Gordon’s books, the time you’ve spent reading this post won’t have been entirely wasted.

Rather to my surprise, since it’s a pretty arcane subject, my last post on the elastic properties of spruce and how these vary according to the orientation of the growth rings attracted a lot of attention. Thanks to everyone who took the trouble to email me with their thoughts or to post comments. Stimulated by your interest, I thought that I might expand on a few things.

Because of the primitive way I carried out these experiments, there must be some questions about the validity of the measurements. One reason why I couldn’t show a difference between the stiffness of the wood in the different growth ring orientations might have been that my measurements weren’t sensitive enough. Another might have been that my preparation of the test bars of wood lacked accuracy or consistency. These possibilities seemed worth checking.

First, I re-planed the 9 test bars so that they were as square and straight and, this time, as uniform in their dimensions as I could reasonably manage.

Then I made an estimate of their stiffness, in the same way as before, by clamping them in a vice one at a time and measuring the downward deflection produced by a load of 2lbs applied 20 cms from the vice jaws. Again, every piece was measured 4 times, rotating it through 90° between measurements. For each individual bar, I calculated the mean deflection (in inches) for the 2 measurements in the different growth ring orientations. 3 days later, I measured them again without reference to the earlier readings. The results are set out in the table below, rounded to the nearest hundredth of an inch.

These results seemed encouragingly consistent. The bars that were stiffer in the first set of measurements came out stiffer in the second set too. So it doesn’t look as if the readings are being swamped by random errors introduced by deficiencies in the experimental set-up or that any differences are due to lack of precision. And the actual values in the 2 sets of measurements were quite close too, so the findings are fairly reproducible.

As you can see, there was some variation in stiffness between bars. The deflections recorded for bars 1 and 4, for example, are somewhere between 10% and 20% less than those recorded for bars 5 and 9. It occurred to me that this might have been because my planing had been inaccurate, but when I checked the dimensions with vernier calipers I didn’t find that the stiffer bars were any larger. It may be that this variation is simply a reflection of how the properties of small pieces of wood differ slightly even when cut from the same board.

Although hardly necessary, since it’s obvious from the table that there’s no consistent difference in stiffness between quarter-sawn and flat-sawn orientations for individual bars, I carried out a straightforward analysis using a paired t test, which confirmed that there was no statistically significant difference. [Difference (quarter sawn minus flat sawn) = -0.004 (95% confidence interval : -0.015 to 0.007) p=0.38 df=8]

Guitar makers often flex wood in their hands to get a feel for its stiffness and I wondered if I would be able to identify the stiffest and the least stiff of the test bars by doing just that. Not a chance! I was quite unable to distinguish differences in stiffness between these bars by feeling how much they bent in my hands. It might be worth doing some more experiments to find out what sort of differences in stiffness can be reliably identified in this way. Perhaps we’re not as good at judging stiffness as we’d like to think?

One final thing, which someone kindly emailed me to point out, is that any shrinkage or expansion across the grain because of a change in moisture content of wood tends to be less at right angles to the growth rings than in parallel with them. So, where the growth rings are orientated vertically in the strut, any change in the width of the strut at the glue line with the soundboard will be smaller than if the growth rings had been orientated horizontally. Now in a guitar it’s hard to see that this will matter much because the struts are small, not usually subject to large changes in humidity and are glued in all sorts of different relations to the direction of grain of the soundboard itself, which is also going to move in response to changes in moisture content. But where the strut lies in the same north-south axis as the grain and growth rings of the soundboard – as, for example, in the bass bars of violins or cellos – I can see that there might be an advantage in keeping the growth rings of the strut in the same orientation as the soundboard. This is the best reason I’ve yet heard for keeping growth rings in bass bars vertical, although as I mentioned in my last post, it wasn’t a rule always followed by the great luthiers of the past.

When working on the top of a guitar, I put the instrument on a carpet covered bench and prop up the neck on a block of wood that has a shallow, foam-lined curve cut into the top – as you can see in the photograph above. But I’ve recently learnt a better method. The device below, made out of 2 semi-circles of 18mm plywood, radius about 3 inches, adjusts itself automatically to the taper of the neck and supports it in a far more stable way.

The danger when using the simple block is that it tips over if the instrument is moved along its longitudinal axis. Of course, one can always clamp the block, but with the new neck cradle there’s no need. I’m grateful to Richard Nice (who invented the plane that I wrote about in my last post) for this bright idea.

Over a year ago, I wrote a post on this blog speculating that one reason why more men played the guitar than women was simply the dimensions of the instrument. It’s not that women aren’t attracted to the guitar; lots start to play it. But the trouble is that as they get better and the music gets more interesting, the stretches that they must make with their left hand become uncomfortably long, if not physically impossible, unless they have a unusually wide finger span.

No one seemed very interested in this theory (I don’t think I received a single comment) but, even so, I thought it would be worth making a smaller guitar with a shorter scale length, a narrower fingerboard and closer string spacing as an experiment. You can see photographs of the instrument here. It has been played by lots of guitarists both professional and amateur, both men and women. Most of them said they liked it and nobody complained that it made too small a sound, although a few of the men found that their fingers were too cramped at the nut end of the fingerboard.

And it did persuade someone to commission a similar instrument, shown below. It too, is a loose copy of a Hauser guitar. The soundboard is spruce and the back and ribs are of Madagascan rosewood (Dalbergia baronii). The bindings and bridge are of Rio rosewood and the rosette and headstock veneer are of English yew. The scale length is 630 mm; the width at the nut is 48mm; and the string spacing at the bridge is 56mm. I’m pleased both with how it looks and how it sounds and I hope its new owner will be too.


A while ago, I wrote about repairing the damaged soundboard of a cedar topped guitar. And I’ve recently had to deal with a similar problem, this time caused by the lid of the case falling on the guitar as it was being lifted out. The damage wasn’t structural but it did leave some conspicuous dents.

The soundboard had been finished by French polishing and I reckoned that simply re-polishing the damaged area would be almost enough. However, first, using a hot (but not too hot) iron and some wet kitchen paper, I steamed out the dents. When dry, I lightly sanded the area before brushing several coats of clear shellac into the places where the polish had been chipped off. After a couple of days to allow it harden, I sanded again with 1500 grit paper to level the area and then re-polished the whole of the lower part of the soundboard in the traditional way using a pad to apply the shellac. Another few days for the shellac to harden, a quick buff up with some burnishing cream and damaged area was almost invisible.

But not completely invisible because, viewed in certain lights, the repaired areas were just identifiable as slightly paler patches. You can see them in the photograph below. I had exactly the same problem with the last repair and I don’t know how to eliminate it. This time I tried exposing the bare wood to UV light for a few hours before applying any shellac but I’m very doubful that it made any difference. Maybe I should have left it under the UV light for longer. If anyone has a better idea, I’d love to hear from them.

The rosette below is made from laburnum, arranged to show the striking contrast between the light coloured sapwood and the dark heartwood. It’s rather more complicated to make than the spalted beech rosette shown in the previous post and a fair degree of accuracy is needed throughout.

The starting point is a small piece of laburnum. This one has been air drying for a couple of years and I reckon that it should be pretty stable by now. I’ve scraped off the wax that covered the endgrain while it was drying.

The first step is to decide how many individual sector shaped pieces to use to complete the circle. I’m planning to use 20 for this rosette, which means that the sides of the billet must be planed to converge at an angle of 18°. That’s hard to manage on the bench top and it’s worth making a cradle to hold the wood while you plane it to size and shape. Go slowly and carefully because it’s important not only that the angle is right but that there’s no taper along the length of the piece. In addition, the width must be right so that the line between the sap wood and the heart wood ends up where you want it to be in the finished rosette.

Having planed the wood to a near perfect prism, it’s sliced on the bandsaw.

The pieces are numbered as they come off, so that they can be put together again in consecutive order.

Here the rosette is being assembled ‘dry’.

It may be necessary to make some fine adjustments with a shooting board and a block plane.

Here, the first piece is being glued and clamped into position on its plywood base. The base has been marked out in pencil to aid positioning of the individual pieces.

As the pieces are glued into place, the rosette nears completion.

Cleaned up and levelled with a finely set block plane.

A while ago, a friend bought himself a lap steel guitar – the sort with a hollow neck, square in section – but became frustrated because he couldn’t find a capo that would fit it. He couldn’t use the usual type of capo, of course, because the hollow neck of the guitar was too thick and too fragile to allow the clamp to work and because the strings were too high over the fingerboard. So I made him this device, which is easy to fit and adjust and works well.

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In case anyone else has a similar problem, I thought it might be worth explaining how it’s made. You’ll need a scrap of hardwood roughly 2.5 x 1 x 3/8 inches in size; a piece of bone or ebony to make the inverted nut; some cork or leather to damp the strings on the headstock side of the capo; a 2.5 inch length of round bar in brass or steel of 1/4 inch diameter; a short length of threaded rod of 1/8 inch diameter; and a small piece of wood or metal or plastic to make a knob with which to turn the threaded rod. You’ll also require a matching tap to cut a thread in the hole of the brass bar.

The photographs below should make the construction clear, so I’m not going to give details. If you have any queries, please email me at info@finelystrung.com. The only thing to watch out for is that the threaded rod that pulls the bar against the underside of the strings shouldn’t be too long or it may damage the fingerboard.

To fit the capo, loosen the screw holding the metal bar – but not so far that the bar becomes detached. Hold the capo with its long axis parallel to the strings and insert the bar between the two middle strings. Then rotate both the capo and the bar through 90 degrees, making sure that the nut side of the capo is orientated to face the bridge. Slide the capo to the desired position and screw it up just tightly enough to produce a clear sound from all the strings.

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The guitar that I have been writing about in my last few posts is now, more or less, completed. It’s finished with French polish, which will benefit from a final burnishing in a couple of weeks time when it has got fully hard. But I couldn’t wait any longer to string it up and hear how it sounds. The back and ribs are zebrano and the soundboard is European spruce. The binding is Rio rosewood and maple, and the soundhole rosette and headstock veneer are spalted beech. I’m pleased with how it has worked out, though perhaps I got carried away when it came to the rosette, which might have been more elegant if the diameter had been a little less. Below are a few photographs of the completed instrument.

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Looking around for more on V-joints, I found Gary Demos’ site where he describes not only the construction of the joint but how he made a copy of a Panormo guitar. It’s a fine looking instrument and there are a few mp3 files that show that it sounds very good as well.

Cumpiano’s website has a brief discussion of the merits of the V-joint versus the scarf joint too. (You’ll need to scroll down a bit to find it.) I enjoyed his comment:

If you use a v-joint people will shower you with praises for your skill and those in the know will guess that you don’t have to make a living at making guitars.

There’s probably some truth in that. I’ve always admired Cumpiano’s down to earth approach to guitar making and his refusal to subscribe to anything that can’t be properly explained. See, for example, his courteous but uncompromising dismissal of the mystique of tap tone tuning.

Still, in the interests of historical accuracy, I’m going to pursue the V-joint a bit further. It seemed worth shaping the neck and headstock of my trial joint to get an idea of what it would look like on a finished instrument. In reality, it doesn’t look quite as good as the photographs suggest. At this resolution, glue lines, which in places are wider than they should be, don’t show up. But I’ve discovered two useful things: first, that the joint isn’t impossibly difficult to make and second, that it’s certainly strong enough.

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Following on from my recent experiment with a small guitar, I’ve been thinking about going a stage further and making a copy of a 19th century guitar of the sort for which Panormo is famous. There’s one in the Edinburgh University collection of historic musical instruments and, rather helpfully, there’s a measured drawing available. The collection’s website has fierce warnings about all the content being copyright so I haven’t posted a photograph, but you can see the instrument by clicking here.

The neck of this guitar joins the head in a traditional V-joint. This isn’t a technique that I’ve ever used before so I’ve been trying it out, partly to get my hand in for making it and partly to reassure myself that the joint is stronger than it looks. There’s a good illustrated article on making V-joints on the Official Luthiers Forum, although you may have to register with the forum to get access. The geometry of the joint isn’t really very complicated but, on the other hand, it isn’t entirely straightforward either. The article explains it well.

The photograph below shows my rough first attempt being glued up. Hot hide glue is the correct stuff to use but, for this trial run, I substituted Titebond.

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Here it is with the clamps off.

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And after cleaning it up.

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And trying to break it.

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I wondered, in view of the endgrain gluing surfaces of the joint, whether the joint would be strong enough. So I played around, first by loading it with a 20kg weight and then by putting it in the vice and pulling on it as hard as I could. I couldn’t shift it and now feel entirely confident that it’s up to the job.

The binding is made from sawn veneers of ebony and maple. The photograph below shows a true edge being planed using a shooting board before using the bandsaw to slice off a narrow strip.

Here, a border of maple is being glued to the ebony in a shop-made clamping device.

Below is a strip of the finished binding, bent and ready to be glued into the ledge already routed on the guitar.

The great photographer, Henri Cartier-Bresson, is said never to have re-arranged a scene or cropped a negative. It was, I suppose, his entirely admirable desire to show things as they actually were rather than how they might have been. Of course, being French, he dressed it up in fancy language. “Il n’y a rien dans ce monde qui n’ait un moment decisif” was how he put it.

Why do I bore you with this? Well, because yesterday afternoon when I was about to take a photograph of the struts being glued onto the soundboard, I caught myself on the verge of tidying the bench before the shot. Why on earth did I think that was necessary? I’m not trying to write an article for one of those wood-working magazines where, if the pictures are anything to go by, projects seem to reach completion without a tool being removed from a rack or a shaving falling to the floor.

Anyway, I stopped myself just in time. Here is where I’ve got to with the guitar that I’m working on at the moment.

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