Luthierie in the time of Covid
With the arrival of Corona Virus I realized that business would be slow for a while so I decided to take a little time out for some of the violin related projects that I could never quite find the time for. The idea of making myself another guitar had been brewing for sometime. The first conventional instrument that I made, about 40 years ago, was a steel string guitar, I had stopped playing it about twenty years ago but recently had fallen in love with the sound and feel of nylon strings.
With the impending lock-down I needed to get materials quickly before suppliers stopped shipping, but I didn’t know what to order. There were choices to make about models and woods and I quickly realized that I knew almost nothing about guitars. I was reluctant to go on the web because I knew that there would be endless, likely contradictory, information and I would probably stall out. I needed to talk directly with an expert, so I called on my friend Richard Prenkert.
Finding materials and information….quick!
Richard is a long established and highly respected classical guitar maker. I went to visit him at his shop outside Sebastopol, hoping for a little guidance on wood choice and bracing patterns. I came away with way more than I had hoped for. Not only did Richard answer all my questions, he let me pick some wood from his stock and loaned me books and plans. In discussing wood, I learned that the two most viable choices were red cedar or Englemann spruce. The red cedar would tend to play more easily straight away, whereas the Englemann would be a little more robust but would mature in tone. I liked the concept of the Englemann but was a little wary of it because I had used some for cellos and found it so light that I needed to leave it almost 20% thicker to get the results that I wanted. I was torn over the Englemann / cedar choice until I tried one of Richard’s Englemann guitars which was the the clearest, warmest nylon string instrument that I had ever played. He also had a cedar topped guitar but the choice for me was clear. Also at that moment of trying Richard’s guitars, any thoughts that I had had of doing anything experimental with my new guitar went out the window. I wanted something approaching that quality of sound, so there was no point in doing anything unusual. I would go with traditionally favored woods and designs.
The final gift I got from Richard, was as valuable as anything else: he allowed me to handle and flex some tops in preparation. They were way more delicate than I had expected. The way they felt in the hand gave me a lot of information, in a way that drawings and numbers just don’t.
The wood. Indian rosewood for the back and sides, Englemann Spruce for the top. Richard provided a mahogany neck but I ended up using some cherry that I’d used before on cello and violas, and I liked working with.
I worked from drawings of a guitar by Hermann Hauser, of München, in 1937. It was made under the guidance or direction of Andreas Segovia and it became the maestro’s favorite instrument. I pretty much followed the plans for dimensions, though I did beef up the three central fan braces, and the cross braces in the upper bout that support the fingerboard. There is a trade off between responsiveness and physical stability. I have a good sense of this in the violin arena, but in Guitar World the forces from the strings and the structures designed to resist them are foreign to me. This guitar appears to me to be incredibly lightly built, and that made me nervous. However, the original guitar served and survived for many years so I assume the dimensions are adequate. All of this led me to think about the structural and functional differences between the guitars and violins and I wrote a blog post about it.
In a major divergence from Hauser’s instrument, I added a cut-away in the body, allowing access to the more exotic reaches of the fretboard. There was a little worry about the body’s air resonance being negatively affected ….. but I just wanted to do it, partly because of the challenge in bending the sides.
Assembling the top was a lot of fun, and nothing like making a violin top. No aerobic carving and sculpting arches involved, everything is flat and easy. The process reminded me of making balsa wood model aircraft when I was a kid, and the finished top felt almost as light.
I had enough violin repair clamps to attach two struts at a time. The wooden counter forms that I clamped into have a radius to them, a deflection of 5mm over their 380mm length. Clamping the braces against the curve causes the top and back to have a slight dome which stiffens them without adding weight. The dome is also visually appealing.
The neck on a classical guitar is a lovely thing. It starts from a narrowly pointed gothic arch where it meets the back. It forms a sharp ridge which mellows as it sweeps down, turning the corner and blending into the soft U-section of the neck. Very sculptural and one of the things I was most looking forward to working on. The neck heel also has some moderately complicated joinery. I was using the “Spanish” construction method, where the neck is built directly into the body, the guitar sides slipping into slots in the side of the neck. In the “Other” construction method, the body is finished first and the neck inserted afterwards with a mortise and tenon joint. That method tends to involve using large, time and space-consuming molds. The Spanish method is more free form and easily adaptable.
The blond circular plug you can see just above the heel is the result of a router accident. I don’t use routers a lot because, while they can save a lot of time, they can also make a big mess very quickly. In this case I was cutting a slot for a graphite stiffening rod to be inserted under the finger board. I was cutting along merrily when the sound of the router suddenly changed. I stopped the motor and carefully peered under the router base at the blade and was astonished to find that it was entirely gone. I’m used to setting down hand tools and losing them in mid job, but this was a new phenomena. Then I noticed the hole through the back of the neck. Apparently the spiral cutter that I was using was loose in the chuck and when it got free, it kept spinning and dragged itself straight down through the the back of the neck.
I didn’t feel too bad about this accident. If it had happened on one of my fiddles for sale, that would have been an entirely different matter and I would have made a new neck straight away. But as the guitar is for me, I thought I would make a feature of it. Later, as I was shaping the neck, more of the damage was revealed and I fitted a larger, tear-shaped patch in matching cherry to cover it.
At the other end of the neck, the “head” is not nearly as much fun as the “heel”. I had thought of using Pegheds, the mechanical violin-type tuners, and making the head like a Flamenco guitar, and in retrospect I wish I had done that. The traditional nylon string tuners are tricky to fit because they are ganged together on a mounting plate, and the receiving holes have to be precisely cut or the pegs won’t fit. I took my time and they turned out just right, but it’s the kind of engineering/woodwork that I don’t really care for. Pegheds next time.
The top of the headstock usually ends in a decorative flourish. Guitar makers usually come up with their own design for this and it becomes a signature. I wasn’t very interested in starting a new brand so just I copied Hauser’s design. Later though, I got swept into a decorating vortex and I ended up modifying the design.
Assembly. The neck was first attached then the sides fitted to the neck and top. The side-to-top joint was reinforced by gluing a series of individual blocks or “tentellones” into the corner. The other edge of the sides was reinforced with a continuous lining, as in a violin. For the linings and tentellones, I used the red willow favored by Stradivari for his blocks and linings.
With the body closed, it was time to finish the edges with binding to hide and protect the corner joins. After the recent reminder about the perils of routers, I didn’t even think of using one to put in the bindings. Instead I reached for my trusty purfling cutter and did the job by hand.
Decorating the guitar took a long time, maybe a week, and it made me wonder, once again, at the amount of time we put into the appearance of our instruments, when all the additional effort does nothing at all to benefit the sound. The only explanation I can come up with for this is that Love is not a rational thing. In the violin world, gratuitous decoration has been very formalized and we all do pretty much the same scroll and the same purfling. Where violin makers do go crazy though is in “antiquing” where a really meticulous job usually doubles the hours that go into making the instrument.
The decorating slippery slope started for me with the bindings which are functional but also decorative. Bindings can get quite fancy. I’m a very shy musician and a fully blinged-out instrument would be just too much hat for me, so I decided to use violin purfling, which is fairly austere, and I also thought using it would be a nice nod to my day job. Once I’d gotten stripes running around the body, there was a problem with terminating them at the button. Because of the cut-away they were pointing in different directions. I could have run them straight across the button and joined them, but with a Spanish style neck the back wood continues up into the button (as it does on a violin), and there is some kudos in that. So I came up with the idea of splitting the back center-seam stripe and joining it with the binding. I was quite pleased with that but it made the button, which is the focal point of the back, disappear. At that point I was obliged to throw in some shell to bring the attention back to the button. I thought the inlay worked passably well but now the back was out of balance with the rest of the instrument, I was going to have to decorate the headstock. This whole process was feeling out of control. It was rather like getting a bad tattoo and having to get another to hide or balance the first.
All the decorations focus at the button. Notice how the side at the cut-away has different curves at top and bottom, so that it can blend smoothly into the neck root.
Revisiting the head stock, I decided to try and do something that reflected the gothic arch of the button. There was only room on the existing head for a broad arch, but it was quite pleasant and resembled the dome on a mosque. I added an ogee curve to either side of the dome and it took on a Indian flavor. Adding some crudely executed purfling to highlight the outline enhanced the Indian effect.
I was quite pleased with the gothic-ogee combination so I repeated it at the end of the fingerboard and I think it worked quite well. It parallels the diagonal of the cut-away and breaks the fearful symmetry of the rosette.
The rosette is also made from violin purfling. Very complex mosaic patterned rosettes are almost the rule in classical guitars but this one harks back to the instruments of Antonio de Torres, the grand daddy of modern Spanish guitar making.
The guitar is now ready to start varnishing, but first it will spend a couple of weeks in the UV cabinet to mellow out the white of the top.