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Model C-16 Venetian Cutaway Myrtlewood and Sitka Spruce

Cozad C-16 Body Complete

Specifications:

  • Body Style: C-16 (Small Jumbo Venetian Cutaway)
  • Upper Bout: 11.75″
  • Waist: 9.5″
  • Lower Bout: 16″
  • Body Length: 20″
  • Body Depth (Tail block): 4.5″
  • Scale Length: 25.4″
  • Soundboard: Sitka Spruce
  • Back and Sides: Oregon Myrtle
  • Bracing: Laminated Adirondack Red Spruce and East Indian Rosewood
  • Bracing pattern: Back - Progressive, Soundboard - Conventional X
  • Binding: Ceylon Ebony
  • Soundhole Binding: Ceylon Ebony
  • Rosette: Oregon Myrtle
  • Neck: 5-piece Mahogany
  • Fingerboard: Macassar Ebony
  • Fingerboard Inlay: Oregon Myrtle
  • Headplate: Gabon Ebony
  • Bridge: Macassar Ebony
  • End graft: Gabon Ebony

Most people would acknowledge that a given piece of wood, cut from what was once a living tree, is unique, as in, no two pieces of wood are identical. But some trees seem to offer more visual distinction than others, and Oregon Myrtle is right up there at the top of that list. In fact, it is extremely difficult to create two "matching" guitars if Myrtlewood has been chosen for the back and sides. I, for one, find that to be a good thing and revel in the distinction. The wood I selected for this particular guitar exhibits pleasing striping and has a visually interesting spalted heartwood appearance down the center.

Cozad C-16 Myrtle Back
Oregon Myrtle back

I rely on my electric Side Bender for the task of bending cutaway sides.

Cozad C-16 Bending Sides Manually
Bending sides manually

My electric bender takes nearly 20 minutes to come to full temperature. While markedly slower than an iron pipe and propane torch, the absence of an open flame provides for an added sense of safety. But you still have to pay attention - whatever you do, don’t absent-mindedly back into one of these while it is at temperature...Ouch!

Bending Burn
Burned while bending

For determining the shape of the cutaway side, I rely heavily on my bending templates. Think of them as the doughnut hole, or what was removed from the inside of the guitar body mold. These are constructed separately using MDF and serve as both a model during the bending process as well as a clamping base.

Should you decide to employ a bending template, consider it’s dimensions: It should be the size of the body mold less the thickness of the sides. Do Not simply trace the corresponding body mold or soundboard template, or you will end up with sides that are too large. While you may be able to force them into your mold, you would be introducing undesirable stress on the instrument.

Cozad C-16 Bending Template
Bending template

By employing an iterative process of bend a little, fit a little I am able to produce a very stable and accurately bent side.

Cozad C-16 Cutaway Side on Bending Template
Cutaway side on bending template

If I am not in a hurry, sides and/or wood binding (Ebony binding in this photo) having been bent via steam, the blanket bender, or the electric bender, are clamped onto a corresponding bending template and allowed to rest overnight.

Cozad C-16 Binding Form
Binding form
Cozad C-16 Binding Form Closeup
Binding form closeup

Once the sides are bent satisfactorily they are held in place in the body mold where they will (typically) reside for the duration of the body construction. You can view an article here where I detail the steps of my body mold construction. Both the tail block and neck block are cut, shaped, drilled and glued onto the sides.

Cozad C-16 Sides in the mold
Sides in the mold

Kerfing is bent prior to attaching. I have been successful in lightly wetting (not soaking) the kerfing, gently forming it around the bending template, holding it in place and allowing it to dry. Additional cuts are made to allow for tighter bends at the cutaway.

Cozad C-16 Bending Kerfing
Bending the kerfing

After the kerfing has thoroughly dried it is glued into place along the rim of the sides.

Cozad C-16 Clamping Kerfing
Clamping the kerfing
Cozad C-16 Kerfing Closeup
Kerfing closeup

Here I have carefully removed the completed sides from the mold, to show how the guitar’s shape has been established and the sides are now ready to receive the back.

Cozad C-16 Sides Complete
Sides Care complete

A sneak peek at what is coming...

Cozad C-16 Back Sneak Peek
Back sneak peek

These days I prefer a laminated brace, as this can result in a thinner, lighter and stiffer end product. This can make a noticeable difference, weight-wise, especially when using a heavy hardwood for the back and sides. For this guitar I chose a combination of Rosewood and Adirondack Red Spruce. I include a primary transverse brace on both the soundboard and the back, and this is formed by sandwiching Spruce between two layers of Rosewood. The balance of this guitar’s bracing is constructed by sandwiching Rosewood between two layers of Spruce.

Cozad C-16 Rosewood Adi Glueup
Rosewood Adi glue-up

When dry, the laminated product is ripped back into individual braces. The process then continues as it would with common Spruce-only bracing, with extra care being afforded while shaping to avoid the cross-grain tearout

Cozad C-16 Rosewood Adi Braces
Rosewood Adi braces

The braces are glued to the back in a fanned pattern resembling the open fingers of the hand. This pattern results in a relatively stiffly braced back, which produces a resonance that is noticeably higher than that of the soundboard.

Cozad C-16 Back Bracing
Back bracing

The back is glued to the sides, having notched the kerfing to receive the thickness of the bracing at the edges. These braces are then resting on a ledge formed by the kerfing at the sides, akin to a joist resting on a wall.

Cozad C-16 Back Glueup
Back glue-up

Small braces are added to the sides at the position of the back braces. These act to support the sides and, as with tape, minimize the risk of the sides splitting along the grain.

Side braces may also assist in transference of the kinetic energy generated by the strings to the back plate.

Cozad C-16 Back and Sides Complete
Back and sides complete

The Spruce soundboard was routed to receive a ring cut from an unused section of the back plate. Purfling was added around the outside edge of the ring.

Cozad C-16 Soundboard with Rosette
Soundboard with rosette

Reinforcement is added to the back (inside) of the soundboard. Traditionally, small braces and/or plates are used for this purpose. I prefer to use a hardwood ring. This serves a dual purpose: adding comprehensive reinforcement while also providing support for a wider soundhole binding.

Cozad C-16 Soundhole Reinforced and Bound
Soundhole reinforced and bound

Ebony, being particularly short-grained and brittle, is not an easy wood to bend. Nevertheless, it is one of my favorite choices for binding. I have found Ceylon (Indian) Ebony to be much more forgiving when bending than Gabon (African) Ebony, and tend to use it more often. I have a repeatable method for forming it around the soundhole. First, I sand a strip of binding to approximately half the thickness used to bind the edges of the body. While this definitely aids in preventing breakage, the primary driver behind thinning this piece is my discovery that I simply do not care for the look of a thick soundhole binding.

Soundhole Binding Strip
Soundhole Binding Strip

Next, I drop the piece of binding into a pot of simmering water. A minute or two in the hot bath has proven sufficient for my purposes. I remove the now malleable strip from the water, wipe away excess water, and immediately inset the strip into a routed circle in a plywood form. The routed channel is wide enough to allow the strip to overlap where the ends meet. This is left to dry thoroughly.

Soundhole Binding in Form
Soundhole Binding in Form

Cut to size and glued in place, the soundhole binding is a welcome visual addition.

Bound Soundhole
Bound Soundhole

Braces for the soundboard, having been routed to rough shape, are positioned and glued in the go-bar deck.

Cozad C-16 Soundboard Brace Glueup
Soundboard brace glue-up

Time is now devoted to shaping and/or tapering, removing unwanted bracing material, using a razor-sharp chisel. Part of the objective is to provide sufficient support to counter the pull of the strings while reducing the sound-deadening impact of added wood and glue. The other objective is to coordinate the transference of the kinetic energy generated by the strings across the soundboard. Do it right and you really smile when you pluck those strings for the very first time.

A carbon fiber fingerboard patch is epoxied in place, shaped to accommodate the cutaway, and adding a Rosewood bridgeplate completes this soundboard.

Cozad C-16 Soundboard Complete
Carbon fiber fingerboard patch

As this photo reveals, the laminated bracing requires a minimal usage of wood, reducing overall mass. Aesthetically, it is a clean look.

Cozad C-16 Soundboard Complete
Soundboard Complete

After the soundboard is glued to the sides I trim the excess material (plate and braces) off the guitar body.

Cozad C-16 Back and Soundboard Trim
Back and soundboard after trimming

The end graft is added to the body.

Cozad C-16 End Graft
End graft

A hole is drilled through the end graft, sides and tail block to accommodate and end pin.

Cozad C-16 End Pin Hole
End pin hole

For a cutaway body, I prefer to manually route and add binding where the cutaway meets the neck *before* routing the binding and purfling channels around the perimeter of the body using the stationary binding router.

Cozad C-16 Binding First Steps
Binding first steps

Dried glue is removed and binding is carefully blended into the body using a scraper.

Cozad C-16 Binding Scraped
Binding Scraped

This body is mounted onto a sled, leveled, and rotated across the router which is equipped with a depth stop and glides on a vertical rail. The process is the same for the soundboard side and the back.

Cozad C-16 Binding Channel Routing
Binding channel routing

Mise en place - With everything staged the back can now be bound. Glue is applied to the purfling strips, binding, and binding channels. The binding and purfling is carefully fitted to the body and held in place with strapping tape until dry. Careful attention is paid at this point to tightly securing the binding to the body and eliminating any gaps.

Cozad C-16 Binding the Back
Binding the back
Cozad C-16 Binding Held With Tape
Binding held with tape

It is time to start on the neck which is cut on the bandsaw from a laminated Mahogany block.

Cozad C-16 Necks After Bandsaw
Necks after bandsaw

The next step is to inlay two carbon fiber rods into the neck. This lightens the neck while adding significant stiffness, both desirable attributes. The grooves are cut on the router table.

Cozad C-16 Carbon Fiber Neck Support
Carbon fiber neck support

Epoxy provides a great bond between the carbon fiber and the wood, though protein glues such as Hide glue and Fish glue have also proven to be effective.

Cozad C-16 Carbon Fiber Neck Support Epoxied in Place
Carbon fiber neck support epoxied in place

Once the epoxy is cured, the neck gets a slot for the truss rod using a spiral bit at the router table. This is a stop dado, as in, the slot does not extend all the way up through the headstock. That extra bit of wood that stays intact, in conjunction with the carbon fiber struts that run alongside the truss rod slot, provide extra protection to the headstock against damage.

Cozad C-16 Truss Rod Slot
Truss rod slot

With the bottom side sanded perfectly flat, the Macassar Ebony fingerboard is first planed square using a shooting board.

Cozad C-16 Fingerboard Preparation
Fingerboard preparation

I constructed a fingerboard slotting jig to accompany a steel fret slot template which is temporarily attached to the top side of the fingerboard stock using double-sided tape. The steel template follows a pin that resides permanently in the tablesaw sled. This approach ensures consistently accurate cuts, essential for proper fret placement.

Cozad C-16 Fingerboard Slotting Jig
Fingerboard slotting jig

With the fret slots cut it is time to radius the fingerboard. I accomplish this by attaching the fingerboard to a simple jig that allows me to rotate the fingerboard across a predetermined radius as I pass the entire platform under the drum sander.

Cozad C-16 Fingerboard Radiusing Jig
Fingerboard radiusing jig

Once the fingerboard is radiused, it is cut along its length on both sides, relative to the centerline, to achieve its final shape. The need to make the fingerboard narrower at the nut end than it is where the neck meets the body presents yet one more opportunity for precision measurements, cuts and planing. As I have chosen to add binding to this fingerboard, enclosing the fret ends, the fingerboard is actually cut even narrower than its finished dimensions in order to accommodate the width of the binding. The binding is glued and clamped in place, then allowed to dry overnight.

Cozad C-16 Binding the Fingerboard
Binding the fingerboard

The effort pays off, as the resultant product shows.

Cozad C-16 Bound Fingerboard
Bound fingerboard

I offer two bridge styles, a classic pinned bridge requiring holes through the soundboard, and a pinless bridge where the strings sit completely above the soundboard.

The pinned bridge:

A bridge blank is cut from the same wood as the fingerboard, in this case Macassar Ebony. After squaring the bridge blank in the same way the fingerboard was squared, a template is attached using double-sided tape.

Cozad C-16 Bridge Template
Bridge template

The bridge blank is secured into a steel jig using a locating pin that aligns the bridge pin holes of the template with the fixed holes of the steel jig.

Cozad C-16 Bridge Pin Hole Jig
Bridge pin hole jig

Viewing between the steel jig and the template, that dark spot in the center of the photo is the locating pin, seen resting perfectly in its corresponding hole.

Cozad C-16 Bridge Pin Hole Locating Pin
Bridge pin hole locating pin

Tightening a bolt at either end of the steel jig clamps the bridge blank securely in place.

Cozad C-16 Bridge Blank Clamped into Jig
Bridge blank clamped into jig

A brad point drill will pass through the alignment hole in the top of the steel jig, through the alignment hole in the template, bore a hole through the bridge blank, and emerge into the corresponding alignment hole in the base of the steel jig.

Cozad C-16 Bridge Pin Hole Jig with Drill
Bridge pin hole jig with drill

Perfectly spaced, precision-drilled bridge pin holes each and every time.

Cozad C-16 Bridge Pin Holes
Bridge pin holes

A view of the underside of the bridge demonstrates the value of this zero-clearance jig; no blowout.

Underside of Bridge
Underside of bridge

I rough out the bridge blank close to the template at the band saw. Using a pattern bit at the router table I am able to follow the template and precision trim the blank to my desired shape.

Bridge Shaped
Bridge shaped

The pinless bridge:

The pinless bridge gets cut from a blank using a template in the same way a pinned bridge does.

Pinless Bridge Template
Pinless bridge template

The back edge of the bridge is relieved using a router to receive the ball ends of the strings.

Pinless Bridge Back Edge
Pinless bridge back edge

The shaped bridge is secured in a tapered gig and holes are drilled from the back edge, through the bridge, and out the top of the bridge (behind the saddle).

Pinless Bridge Holes
Pinless bridge holes

The wings are thinned at the oscillating sander in the same manner in which the pinned bridge’s wings are thinned.

Pinless Bridge Wings
Pinless bridge wings

A small, radiused channel is routed into the top of the bridge where the strings emerge, using a roundover bit. This lightens the overall weight of the bridge and increases the break angle of the strings up over the saddle.

Pinless Bridge Channel
Pinless bridge channel

The result is a bridge that requires no holes be drilled into the soundboard, and no pins need be retained while performing string changes.

Pinless Bridge
Pinless bridge

An Ebony headplate is glued on to the neck stock and shaped using a template (using a method similar to that used for making the bridge). The logo is cut from Myrtle and inlaid into the headstock.

Headstock
Headstock

The neck is fit to the body. A mortise is cut into the neck block and a tenon is cut into the heel of the neck.

Neck To Body
Neck To Body

The fingerboard is glued to the neck, encasing a truss rod. Here, an aluminum fixture having plastic cauls is used to clamp the fingerboard in place while the glue dries.

Fingerboard Clamp
Fingerboard Clamp

This close-up reveals more of the engineering of a bolt-on neck. You can clearly see the tenon projecting from the heel and containing two threaded inserts (cross dowels may be used in place of threaded inserts, but are heavier in weight). The truss rod sits tightly up against the underside of the fingerboard which also contains two ultra-lightweight Nylon bolts used to secure the fingerboard extension down to the soundboard. The blue aluminum fixture with black plastic cauls is clamped atop the fingerboard.

Fingerboard Clamp
Fingerboard Clamp

The neck is carved and shaped by hand using a spokeshave, a rasp and sandpaper. Yes, in this age of the ubiquitous CNC, I still shape each and every neck by hand. A plastic template is used to check target dimensions along the neck. Planing, filing or sanding too much off the neck at this stage would be a total disaster!

Shaped Neck
Shaped Neck

The fingerboard gets inlayed with fret markers and ornamentation. Earlier, as I was constructing the body, I had envisioned simple white shell dots with Myrtle wood filigree, so I set about to create what I saw in my mind’s eye. I drew the pattern on paper and, once satisfied, transferred it onto waste sections from the back.

Fingerboard Inlay
Fingerboard Inlay

The neck gets bolt on and the fingerboard extension gets bolted down.

Neck Attached
Neck Attached

Are you interested in learning more about this guitar? or would you like to inquire about a custom made Cozad guitar?

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