H-5 Mandola tops and backs.  Click on image to see Mandola Gallery.
Precise cnc carving on the F-5 scroll means the difficult work is nearly done.  Click on the image above to see the Mandolin Gallery.

Finding Trees, Cutting Logs
and Preparing Lumber

This is where it all starts, in the middle of the woods in Maine, finding the holy grail of acoustic instrument tonewoods, Adirondack Red Spruce.  Most years I spend several days searching for trees that will yield instrument grade wood for use on my own instruments and to sell to other luthiers.

Video from a 2013 Logging Trip.  This is a smaller tree that will be used for mandolin tops.

Logs are cut into blocks and the blocks are split on site.  The ends are sealed with wax to keep the log from splitting as it dries.

The wedges are cut on a band saw.  Some are cut for flat top instruments like dreadnought acoustic guitars and some are cut for archtop instruments like the Double Bass Guitar or mandolin.

The curly red maple used for backs also comes from Maine where I have a friend in the logging industry who keeps an eye out for nice logs.

The wood is first stacked with narrow pieces of wood in between each piece to air-dry for several months, then stored on racks for at least two years before use.  Most tops I use are well over ten years old.

Design and Prototype

Like a double bass, this instrument is fully acoustic.  There is no "block" under the bridge, the top is arched to support the pressure of the strings.  In order to design a top that could support the pressure and produce excellent tone, a jig was built with the ability to quickly test different tops.

The jig has a plywood body and neck.  A large pocket is routed to accept a top plate and hold it in place without glue.  Piezo discs are temporarily taped to the top and it is strung up.

To succeed, the design had to capture as much double bass sound and feel as possible in an electric bass sized instrument.  I wanted it to be loud enough unplugged to sound good while practicing and more importantly, amplify well.  Finally, it had to be aesthetically pleasing.

It took eleven tops with varying arching, graduations (thickness at different points) and bracing to arrive at one that had the strength needed to support the pressure of the strings while producing a full, rich, balanced sound.

Making the Neck

Once the top was finalized building the complete bass began.  The neck and the body must fit together perfectly.  The best way is to make the neck first, then adjust the neck pocket until it's perfect.  So, neck blanks are made, truss rods made and installed, the basic profile is cut, and the top of the neck and headstock area are planed flat with a hand plane.

The neck blank is placed on a jig designed to cut the angled heel with a cnc router.

Mother of Pearl inlay is cut and inlaid into the headstock overlay which is then glued to the neck.

The headstock is cut out.

After rough shaping the back of the neck fingerboards are made and glued on.

Making the Body

The body consists of three main parts.  The top, the back and the core.  The core is prepared by joining two pieces of Alder or Poplar wide enough to make a body.

Red Spruce sets are joined for the tops.

And Curly Maple sets are joined for the backs.

The top is carved.

Most bodies are made with a poplar core and maple back,  The one pictured on the left is solid mahogany.  The backs are carved inside:

And outside.

The top is temporarily attached to the back and the neck pocket is routed.

Neck is checked for perfect fit.

Top is glued to the back/sides.

Parts, Finishing and
Final Assembly

Various parts including the tailpiece, bridge and gut anchor pictured to the left are fabricated.

Nitrocellulose lacquer finish is applied, starting with the sunburst shading, followed by three to four coats of clear.  The goal is to have the thinnest finish possible that looks good, protects the instrument and does not inhibit sound.  People can argue all day whether finish affects sound on electric instruments, but it's a fact that a heavy finish will kill the sound on an acoustic instrument.

Final assembly includes setting the neck into the body, installing the electronics, tuners, nut, bridge, tailpiece, knobs, strings, and various other parts.

The bass is tested, played and any final adjustments are made before shipping.  And that's it.  Time to start another three DBGs!