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  • Home
  • About
  • Materials
  • Design
  • Gallery
    • Current Shop Happenings
    • 2018 – Present
    • 2014 – 2017
    • 2008 – 2013
  • Contact and Ordering
GLYCERYL ROSINATE GROUND (a finishing experiment GLYCERYL ROSINATE GROUND

(a finishing experiment that refused to stay theoretical)

I’ve been thinking a lot about finishes lately — not just as protection or cosmetics, but as active components of the mechanical system of the instrument.

A guitar top doesn’t care how beautiful a finish is. It only responds to mass, stiffness, and damping.

Any finish that adds weight without contributing stiffness reduces efficiency. In plate-acoustic terms, it lowers the stiffness-to-mass ratio, reduces the radiation ratio, and increases energy lost to internal friction. From the top’s point of view, that’s just a tax on motion — and therefore on sound.

That idea sent me down a rabbit hole of Carrollian proportions, complete with chemistry textbooks, 19th-century varnish treatises, metal salts, a water bath, one small flirtation with fire, and more than a little tree sap.

Why rosin? And why not raw rosin?

Rosin has been around forever. Violin makers know it well. But brushed-on raw rosin is brittle, acidic, and chemically unstable — especially in thin films. On guitars, it’s essentially a betrayal waiting to happen.

The solution wasn’t to apply rosin directly — it was to change its chemistry.

By converting rosin into glyceryl rosinate, its material behavior changes fundamentally:
	•	higher glass-transition temperature
	•	reduced acidity
	•	improved film stability
	•	lower internal damping

Same tree gunk. Very different material. Commercially available — and surprisingly absent from the instrument-making world.

(Continued in comments)
Negotiating resonance under duress. Negotiating resonance under duress.
“I’m going round in circles,” he thought. “I hope I’m going the right way.”
— A.A. Milne, Winnie the Pooh
Back on track… Back on track…
Continuing to challenge your own opinions isn’t Continuing to challenge your own opinions isn’t just good practice, it’s the only way a personal design language stays alive.
Challenging your opinions doesn’t mean abandoning your framework; it means stress-testing it.
I’m currently fighting the urge to go out and bu I’m currently fighting the urge to go out and buy every stick of cherry in the Northeast.

The response of this back is immediate, punchy, articulate, and looks like a million bucks. It has that vintage, dry snap with a modern richness I wasn’t expecting.

Sorry to my lumber suppliers in advance.
My recent work lives at the intersection of tradit My recent work lives at the intersection of tradition and intention — between the classical guitar’s deep lineage and the voice of modern players.

I’m after the warmth, depth, and complexity of the great instruments of the past, shaped by a contemporary understanding of structure, mass, and coupling. Modern tools matter, but only insofar as they serve a modern musical voice. Every brace, every thickness, every joint is there for a reason. Not a gram more than necessary.

The goal isn’t reinvention, and it isn’t imitation. It’s a guitar that moves freely, couples efficiently, and speaks clearly — rooted in tradition, confident in the present.

This spruce and cherry guitar is one more step along that path.

If you’re curious what that feels like under the hands, come play it. Instruments like this only really exist once someone sits down and makes music with them.
Gluing the bridge with a vacuum clamp… because m Gluing the bridge with a vacuum clamp… because my anxiety prefers evenly distributed pressure.
It’s that time of year again… Humidity can ma It’s that time of year again…

Humidity can make or break fine wood—whether in a guitar, a piece of furniture, or any other carefully crafted project. Too dry, and cracks can appear. Too wet, and wood swells, warps, or even fails structurally. Getting it right is critical, but most hygrometers are either wildly unreliable or absurdly expensive—and the professional-grade units need constant recalibration.

When we were starting out, we realized the solution wasn’t buying a fancier box—it was going back to the physics. We built a DIY Psychrometer, the same fundamental tool used in labs to calibrate high-end instruments. It’s simple, elegant, and shockingly effective. Measure the air temperature first, then measure how cold a wet sensor gets in strong airflow. You’re literally measuring the air’s ability to absorb moisture.

The result? A lab-quality humidity reading for a few dollars, consistent and reliable, every time. Using the same sensor for both measurements eliminates error, and forcing maximum airflow guarantees true readings. It’s hands-on, it’s precise, and it keeps your instruments happy and safe.

For anyone working with wood, this isn’t just a neat trick—it’s a safeguard. Never trust a gauge you haven’t verified. Monitor consistently, and you’ll protect the long-term integrity of your instruments and projects.
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