I’m certainly not the first person to think about using bamboo to make a guitar – Yamaha produced an acoustic 6 string called an FGB1 a while back, and people have used thick bamboo laminates for electric guitar solid bodies.
The first reason I have for wanting to try bamboo is to do with its merits as an easily renewable material, unlike the hardwoods usually used for acoustic guitars. Many of these are very hard to get hold of as humanity tramples across the planet: Brazilian Rosewod and Koa are just two examples.
Most people know how good a flooring material bamboo makes because of its hardness and pleasant appearance. It’s now available in thick laminated panels for benchtops and furniture making as well.
One thing I don’t yet know about bamboo is how stable it will be with changes in humidity and when it comes under the prolonged stress of string tension. Users of the Yamaha FGB1 talk about having to adjust the neck every week to keep it playable.
Another thing I need to investigate is its acoustic properties – particularly the along grain, cross grain, and torsional moduli of elasticity for the panels I’m using.
Other question from a builder’s point of view are:
- how well I can make the bamboo bend in the side mould?
- will the formaldehyde laminating glue hold up while bending?
- how well will bamboo take machining to fit edge bindings?
- will the formaldehyde glue outgas under heating?
- what thicknesses should I use for the soundbox?
As a starting point, I’m going to make the sides and back of the soundbox out of bamboo while keeping the rest of the structure and materials the same as I usually use – spruce for the top, and Niugini Rosewood for the neck.
I have now got hold of some 4mm thick by 200mm wide vertically laminated panels:
I got it from Bamboo Australia Pty Ltd in South East Queensland. You can order from them on line. Durnford is very interested to see how the bamboo guitar turns out.
So using a renewable resource is my first reason to try bamboo. But I have another reason as well.
What I want to find out is how much effect the timber species the soundbox is made from has on the overall tone of the guitar. The reason I want to try and test this is because I have a suspicion that, when stacked up against all the other factors that determine the tone of a guitar (top bracing, soundboard timber quality, soundhole size, strings, neck bracing system, etc) the effect of the wood making up the sides and back of the soundbox is minimally important.
This is not what most people think, so perhaps I’m quite wrong. Some will spend a fortune on a Brazilian Rosewood guitar, for example, because they believe the tone is unique. But then, concert violinists apparently can’t reliably pick out the sound of a Strad in a blind test. Everything we sense is filtered through our expectations – if you don’t believe me, search out some Derren Brown videos on YouTube (don’t be put off by the Svengali stuff – he’s brilliant at illustrating how much at the mercy of our own expectations and senses we are).
I have read of people who claim they can tell an instrument made with hide glue from one made with plastic resin glue by listening to it. Maybe I’ve just got a dud ear.
Making one bamboo guitar won’t give me a definitive answer, of course, but it’s a step on the way.
I intend to document the building of my bamboo guitar on this blog, and I’ll include my thinking on how to evaluate the results – not a trivial question!