Spanish SteelString – Eco Acoustic

Every great project starts with three main elements. An innovative idea, a transgressive idea and a totally insane idea. However crazy the concepts they must all have a common connection that will hopefully bring everything together in the end. It needs to have structure planning and purpose. In this article I will tell you what those ideas were and the challenges faced, resulting in a project that any normal person would have simply laughed at. However, with any crazy idea the impossible is sometimes, possible (or at least worth trying)

"- What if ...?

- Impossible, that's crazy....

- Let's do it." 

Translation: Clayton Walker et al.



White Eucalyptus is found right across Australia. Aussies have stories, songs, even children’s nursery rhymes that highlight the local eucalyptus trees. Introduced to Spain in the nineteenth century it is a sustainable wood that grows very fast. Some say it was introduced to help with the huge demand to print Franco’s propaganda. Perfect for paper but its colour made it unappreciated in the construction of instruments. That was until Madinter had an epiphany to change that. How do you change the colour of wood and keep its integrity? To give you an idea, the results are not really black, or rosewood-like. They have given this wood a completely unique colour of its own. Read more about the colour changing process here(Pour nos amis français vous pouvez cliquer ici >>>eucalytus_vieilli Madinter)
Somehow, they managed to turn the white Eucalyptus into a wood capable of competing in beauty with any exotic wood. Its properties and hardness, tone and finish are comparable to the best Palosanto. The timber kit we used was a spectacular flamed cut that the camera could not do justice. Our project was underway.


Have you noticed that it's a Spanish guitar with an acoustic neck? They say madness is limitation-free intelligence. Well, a little madness was needed, starting with the thought to hand carve this wood. To give you an idea, its compression force is identical to that of ebony but exceeds its deformation resistance by more than 150Kg per inch. We thought we would start with the back and sides from Eucalyptus. (fantastic to work with but as hard as hell). But we wanted to do more so why not make the neck from the same wood! And we didn’t stop there. We also decided to make the ribs, the butt, the heel, the lid, the linings everything we could from the same material. That was the challenge and what a result!

Detail of the joint in tail block or truss

Through the soundhole you can see the laser engraved upper brace: Úbeda 2020


Thermoprinting has been used in graphic arts for some time but it has never been implemented in the rosette of a guitar. If we are going to build the first guitar in the world entirely from Eucalyptus, then we could make the first iridescent foil rosette to match. A little transgressive by the standards of a classic rosette, but here we have absolute freedom. We looked at various designs, ropes and weaves, even Australian Aboriginal tribal symbols. In the end, the simplest and most logical design, Eucalyptus leaves! The iridescent film in the foil reflects the white light by projecting it as individual colours, just as raindrops form the rainbow. But we wanted a certain range of green tones so the rosette has a filter that eliminates red reflections enhancing silver blues and greens. The filter is invisible and is a little secret that I'm going to keep to myself for the moment... some magic I’ll keep up my sleeve.! The colour and brightness of the finished rosette is impossible to capture with a photograph. The angle at which light affects it creates incredible variations. It's one of those things you have to see to truly appreciate.



Yep, it's made of Eucalyptus! The design is original but follows the common steel string pattern. The saddle is made with an ivory substitute, manufactured by GraphTech. This organic compound is created using oils and products of animal origin. The finished black saddle is the perfect aesthetic for this guitar. The nut is also made of the same material. Both are self-lubricating so that the strings slide and fit perfectly.


There was no other choice for the top. We are all so used to the traditional fir or cedar tops but this was not a traditional guitar... This Eucalyptus top in its natural colour is perfect for this project. In addition to the beautiful vein it has, it has a subtle flame that gives it a certain pearly touch. But wait, there’s more…


Under the top is a variety of acoustic hybrid X-Bracing. 3 rods in a fan-wattage style similar to classical guitar configuration. It was designed to withstand the enormous tension that steel strings bring to the equation and, if you’re wondering about the tonal result, have a look at the video at the end of the article.


It almost goes unnoticed but is possibly the prettiest piece of the instrument. And again, the photos don’t capture it as it really is. When you see it in person you realize the reflections it produces. From different angles, the light becomes dark and then turns to light again. Did I mention what type of wood we used?


Also built using Eucalyptus, carving the heel was an exercise in patience that really tested the art of sharpening tools. We took carving turns!


The purfling’s showcase the full elegance of the eucalyptus. An amazingly natural flame that is difficult to find in other dark woods. These purfling’s frame the wood in a clean and strident way. This instrument already commands attention but the detail, this fine detail, makes this guitar much more than a crazy idea.

There are so many things that make this project special. Madinter's ability to innovate, the challenge of exclusive using Eucalyptus, the hybrid design throughout. The list goes on. This build will forever have a special place in the archives of my workshop. But, in addition to creating the first Ecofriendly Guitar Making Course and sharing it with my student, teacher and friend Clayton Walker, the result is priceless. An incredible project was born and completed out of a ridiculous idea. Thank you Clay, you did it mate!

If you want to know more about this course, clic here.

And by the way, I forgot to mention that we only had 5 days to complete this project? 🙂


  • Top: Eucalyptus
  • Body: Eucalyptus
  • Neck: Eucalyptus
  • Fretboard: Eucalyptus
  • Headstock: Eucalyptus
  • Bridge: Eucalyptus
  • Purflings: Eucalyptus
  • Decorations: Perloid and foil rosette
  • Tuners: DJ Vintage Acoustic
  • Nut: 44mm
  • Scale: 24.3 in
  • Frets: 18
Black Pearl - Fondo

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