Let me preface this article by saying that it is my opinion that a luthier isn’t really a luthier unless they understand and have a pretty solid command over traditional techniques, build styles, and materials. I believe skilled trades work and move forward on solid legs because they are always stepping on the ground that previous generations have made solid. When someone who does not understand tradition tries to make improvements, there is a much higher likelihood they will be “speaking out of school” and end up creating something without a strong foundation. This is where, as a repairman, I see obscure guitars from obscure makers come into my shop with serious structural issues and design features which just don’t make a lot of sense.
Having said that, I think its important, once you have your feet under you in this trade and you have spent your formative years studying and practicing traditionally, that you begin to start thinking outside of those boxes. I think this is especially important for makers who are currently in the earlier stages of their careers. The reason for this is survival. The industry in terms of economics and in terms of natural resources has experienced and will continue to experience massive changes. It will become imperative for younger makers to adapt in many ways if they wish to have long term careers and if they wish for lutherie to remain a vibrant trade. Trends in music, ecology, the timber industry, climate change, global economics all play large roles in this business. To ignore the changes unfolding within those worlds is a mistake. To not be preparing yourself to move with the times is an even bigger mistake.
I’ve found it helpful to look to sources outside of lutherie for better understanding. There is a wealth of knowledge out there about structural integrity and various methods and materials in the worlds of – architecture, aerospace, sailing, golf clubs, fine art, auto and motorcycle engineering, and even fashion, – that a luthier can pull from and extrapolate into better understanding things like string tension on brace structures, long term load fatigues and breaking points.
So with that said, I’ve put at least a moderate amount of effort in recent years into learning about, experimenting with, and ultimately implementing various alternative materials and methods. By no means have I re-invented any wheels or stumbled upon any seismic insights. But I think that learning more about mechanical properties and various methods of construction has helped me to de-mysticize some things and given me some confidence in the future of my craft. I’ll talk here a bit about some of the core things that I’ve learned and am trying to implement more of in my instruments.
First is material. There have been plenty of in-depth articles written about “alternative tonewoods”. I doubt I can improve upon them so I’ll just say a few things in this regard. Whether we are talking about tonewoods or structural components like pick guard mounts what we are really talking about is mechanical property. Mechanical properties (if that phrase is alien to you) are the empirical/measurable properties of a material like density, specific gravity, elastic modulus etc… These are the properties that determine how a material is going to behave under various types of loads, deflections, vibrations etc..
When we understand mechanical properties we get to an understanding of whatever material we are working with that is more reliable, consistent, and grounded than what we end up with when we use subjective adjectives to describe them. Its is more meaningful to say
“This piece of African Mahogany has a specific gravity of .53, a density of .63 (10^3 kg/m^3) and a modulus of elasticity of 1.5 MOE(x10^6 in/lb^2)”
Than it is to say
“Mahogany has a rich warm characteristic with a nice fundamental”
In contrast, that second statement (the one that really is the conversational default amongst instrument makers and buyers) is essentially meaningless. Its meaningless because it doesn’t provide substantial, objective information or data which can then be used in any meaningful way. At its core, the language used in the second statement is simply marketing. Its a flowery and poetic way to describe something void of any real technical info in order to romanticize the wood.
I’m not saying its never appropriate to speak in those terms either. Of course, we don’t want every conversation about instruments (particularly with clients or music lovers) to be an analytical run down of empirical metrics. But as builders, during the process of creating an instrument and choosing materials, it is absolutely a more fruitful way of seeing everything.
Importantly, understanding mechanical properties in this way opens the door to alternative materials. Because when we strip away all the history, nostalgia, iconography, and flowery language and are left with a simple data set as a guide, we can start to see that other woods we aren’t used to using, may have mechanical properties similar to or are even more desirable (in regards to our goals) than that special fairy dust wood from the far reaches of some unheard of jungle.
Mechanical properties are not the only things that matter about wood of course. They are measurable properties of wood… but there are some unmeasurable properties of wood and thats precisely, in my opinion, what makes wood special. There are chaotic elements within the structure of wood, and characteristics which, from piece to piece, can only be translated in a meaningful way by someone who has experience listening to and touching wood in the process of making instruments. A particular piece of wood for example may have a specific density when measured, but that won’t tell you about the size of the winter growth rings or the grain orientation, or any number of other factors which make wood wood. Understanding this is important because it helps us make decisions about when it is or isn’t appropriate to rely on mechanical properties or when it is or isn’t appropriate to rely on our touch and sight instincts. Carbon fiber may, from a purely empirical stance, seem like the perfect material to make a guitar top out of. But every time we do that we notice it lacks something. My take is that what it lacks is what is not measurable in wood.
Looking at mechanical properties and thinking outside of the box in my practice has led me to discover “rocklike” and other similar products which mimic ebony. Mechanically they are the same if not more superior than genuine ebony and aesthetically they look like the best jet black ebony out there. I’ve also begun experimenting using cherry as a neck wood (cherry has almost identical mechanical properties to African mahogany. Its a great, stable, and beautiful neck wood that is domestic and plentiful and almost nobody is using it. how come? Of course i’ve also opened up to carbon fiber, plastics, and other materials. I don’t see the need to use wood for everything. Again, if we strip down all the poetry and just look at properties, we find that each material has optimal uses and there is no reason why we should say no to plastic purfling, for example, for no reason other than tradition.
Another thing that I have become increasingly interested in over the year is lamination. Lamination is simply a method of building up structures with multiple layers. I feel that a lot of people think of construction grade plywood when they think of lamination. Construction grade plywood certainly is an example of lamination, however its really important to understand that its not the only possibility of lamination. Laminations are not all created equal. Some laminations are multiple layers of the same material glued together. Some have alternating grains. some are two skins (exterior layers) that house a core of a different material. Some have thick cores and thin skins. Some have thin cores and thick skins. Some are all wood, while others use wood as a core and steel and carbon fiber as skins. Some use foam core, or cardboard, or other more advanced synthetic materials. Thats not even touching the variances of adhesives and binding agents possible. The possibilities are really pretty endless and what you use will be determined by the goals of the object you are making.
For a long time in the world of manufactured guitars laminations were used chiefly to serve two goals.
1- cut costs. By not using solid pieces of expensive wood and instead using cheaper grade woods as the core materials and a better grade wood just as an aesthetic veneer- or in the case of arch topped instruments being able to get multiple guitars out of a piece of wood that would only make one carved instrument.
2- And in some cases to quickly and easily reduce feedback issues without having to dive into the world of individual voicing and nuance design changes to correct those issues.
As a result, I feel that the most common perception of lamination in guitars is “cheap”. But this just isn’t true. Lamination, as a method performed with goals of improving sound or structure, can be used to great advantage in high end hand crafted instruments. It just depends on how it is utilized.
The possibilities are endless but just to name a few of the ways in which lamination can be utilized in guitars
- Weight reduction without sacrificing strength
- increased stiffness, strength, and flatness of sides
- increased stability of less stable materials
- generally increase stability over time (less potential for cracking)
- Increase strength of components like arch top tailpieces
- add stiffness and load bearing capabilities
- reduction of excess waste of increasingly rarefied materials (ecological)
Those are just some of the benefits I know to be true of laminations depending on how and where on the instrument it is utilized. But there are probably many more potential benefits of incorporating lamination as a method.
Many woodworkers attribute the increase in attributes like strength and stiffness of laminations to things like the adhesive, grain orientation, and evening out of wood defects over many layers. But whats often not discussed is the basic physics of laminations. Its worth understanding at least in laymen terms, how the neutral bending plane (or neutral axis) functions in regards to sheering, compression, tension, and load in order to best utilize lamination and not mis-utilize them.
I’ve been laminating my sides now for 2 years and I can’t see myself ever going back. The process laminating is more labor intensive than just bending a solid side set. There are some additional steps. But in the long run I believe its a time saver because there is less fighting with the sides in the mold (once they are laminated they are rock solid and don’t move around on you), they are dead flat which means less finish sanding, they keep their shape for ever, and it allows for less internal structure like side stiffeners. I’m also experimenting with different ways of laminating tail pieces and pick guards for my arch tops which will minimize my use of hard woods, and ultimately give me more stable and stronger pieces.
The last thing I have time to talk about here is resins and epoxies. Chemistry in this field has evolved tremendously over the last 50 years. Its really a fascinating but somewhat overwhelming world for someone who doesn’t know much about chemistry (me). But I’ve found, through a lot of experimenting, that there are a lot of very neat things, both aesthetically and design oriented but also structurally, that can be accomplished with the use of various resins and epoxies.
I think the most notable advantage we have now is that resins offers us the ability to use woods that we previously wouldn’t have touched. Woods that are very burled, spalted, punky etc… would have previously not been of much use to instruments makers because of their lack or stability and workability. But now, particularly in electric guitar and aesthetic appointments, we can stabilize these woods through the use of resins and turn them into useable and beautiful pieces of wood.
Structurally, I’m still a fan of hide glue, fish glue and the occasional application of wood glue. But for particular things I find that epoxy really does offer some great advantages. I think its important not to over use it because I do believe its application is pretty limited in instruments. But I use it a lot for things like installing carbon fiber, various laminating, and sort of the hidden structural elements I never want to come apart. It also offers some interesting pour filling and finish options.
Anyway… I’ve now spent too much time writing what was supposed to be a short little blurb. I have to get back to work. The three things I mentioned in this article really only scratch the surface. I didn’t talk at all about bamboo which I think will play a big role in instruments down the road, finishes, CNC, or metal. But the point here wasn’t too get too specific or technical, it was more to just bring attention to the importance of opening your doors to what is still considered “alternative” materials and methods of building high end hand made instruments.
I will just close by saying that I think these areas are all worth exploring if you are a young luthier interested in a long career in this craft. I believe that the future of lutherie is going to depend on a nuanced balance between tradition and modern and the smart utilization of “alternative” materials and methods. Not only for ecological reasons but also because, in many of these cases, it just makes for better outcomes. But the ecological pressures is the thing that will force the hand no matter what and I think its better to be prepared for that forced adaptation than to be caught with the pants down.
The real challenge is changing the mindset of guitar buyers on some of these issues… educating them on the advantages and trying to shift the conversation of woods away from the “bell-like chocolatey response and velvety mid range” of a rarefied and increasingly unethical timber to the “very desirable modulus of elasticity and density of this very stable and ecologically more available domestic hardwood”
Cheers and keep the digits