Maudal Musical Machines

Bullfrog 12

The tree

Silver maple · 11th and Indian Hill, Claremont

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The pile

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Early process

The M3 body curve

An archtop normally needs a 9–12° neck break at the body joint to set the strings correctly over the arch — putting a bend in the most heavily stressed connection on the instrument. These bodies curve instead. Top and back are routed in opposing curves on a fixture built for the purpose, so the geometry comes from the body and the neck meets it at zero degrees. Archtop ergonomics, no break at the weak point.

Epoxy filler, before purfling
Routing the back curve — first pass
The fixture that cuts the wrap-around curve
The fixture, continued
Final pass on the top — curving against the back
Concave top jig — final passes
Concave top jig — final passes, cont.
Carving the neck
Carving the neck
Carving the neck
Carving the neck
Carving the neck
Doming the baffle — belt sander and hand drill
Sanding the baffle on the drill press
Inside curves on the drill press
Inside curves, continued
The finished baffle, and what it does
Violin cleats and hot hide glue on the centre seam
Making the cover plate
Making the cover plate
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Finish

On the scale — 4 lbs 10 oz
All colour on, water-sanded flat, before the clear coats
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Tragedy!

Carving the tailpiece
Cutting the string channels — on a fretboard radiusing jig, repurposed
Drilling it
The hood ornament — truss rod cover cut to match, with the tuners just on
Fitted, and the finish underneath it
Stringing up — minutes before

At the moment of first stringing, the tailpiece let go.

The tailpiece, after
The second tailpiece — bloodwood and ebony, a different design

The replacement was a new piece entirely — bloodwood and ebony, a different design. The truss rod cover had been cut to match the first one, so that had to be made again too. Both went on under deadline for the show.

The Instrument

Apr 2025 · Claremont Lewis Museum of Art

Magnetic grounding

A wooden tailpiece usually forces a choice: ground the strings properly, or keep the tailpiece removable. This one drops over a post, and the ground wire emerges through the top just ahead of it, ending in a magnet. A second magnet is inset into the underside of the tailpiece. Lift it off and the circuit breaks; set it back down and it grounds itself.

Grounding through the tailpiece — shown on a multimeter
The Bullfrog 12
The first thing it ever played
Orbelín and the Black Widow — a late mix
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Pre-fitting

Shaped, sanded, sealed — not yet fretted
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