My intention was to tell you all about neck making as it is the very step I’m at with the three guitars I am currently working on. It soon became clear that “Necking” was going cover more that one post, as it should.
The Neck of a guitar is the structural support for the fingerboard, strings, and tuners. It must be light weight, slim, and sufficiently strong. Most all necks are made from Mahogany or Maple. There are varied styles and different methods of construction with several different joint types where the neck meets the body. Most necks should have a truss rod to eliminate bowing, which will also vary in design and installation techniques. Lastly, the fingerboard usually Ebony, Rosewood, Maple, or other very hard wood. Beginning with the wood choice and construction type lets look at these components.
For my necks I use Sapele which is similar to Mahogany and commonly used in instrument construction such as 26 and 36 string harps and Ukulele necks. It has a reddish brown color with nice ribbons down the grain. There are a few basic styles of construction: one piece, two piece with a scarf joint and a single heel block, and multi-piece utilizing a stacked heel block. A one piece neck is cut from a single block of wood. Two-piece and multi-piece necks are cut from a 1×3 board where the multi-piece uses smaller pieces to “stack the heel” while the two-piece has a solid heel block. I use the multi-piece method. Using one board I make the scarf joint, and the heel blocks which are stacked in a specific manner, () , to create ‘one’ heel block. Either type of construction is acceptable and as with most any subject, the more you try to figure out which type is best, the more perplexing, so I say get on with the Necking which leads us to the Joint and I always enjoyed Necking along with a good Joint.
There are several types of neck joints but all are basically a mortise and tenon. Most common is the dovetail mortise and tenon, which is normally made using power tools, however I have seen video of a few talented craftsmen who create this joint by hand. I was humbled. I make mine with a router and jigs which once set up is accurate and reliable. Another type of joint is a rectangular mortise and tenon which can be glued or bolted on. Lastly a dovetail which is bolted on rather than glued. The real task with the union of neck to body is attaining the proper angle. Prior to gluing the neck to the body the headstock must be shaped and tuner mounting holes drilled. Ha! Drilled! Necking with a good joint and Drilled plus, Rods coming up.
Truss Rods are used in guitar necks to eliminate bowing caused by string tension, tension release in the wood or a combination of both. There are two basic types of truss rods, single action or standard and double action or “two way”. A standard rod can only remove ‘upbow’ in a neck where a two way rod can remove ‘back-bow’ as well. I use a standard rod on my acoustics and a two way rod on my electrics. Installation of either type requires routing a channel and creating access either at the headstock or sound hole. Once the rod is securely installed the neck is ready for the Fingerboard. So, on to more Necking and Fingering.
The Fingerboard or Fretboard if you prefer requires a very hard wood such as Rosewood, Maple or Ebony. There are other woods of course that meet the requirement it’s just these are the most popular. I have a nice piece of Persimmon that I am holding onto for the right guitar. Fingerboard blanks are made to 5/16” x 3” x 15” for the acoustic flat top. The finished dimension will be up to 1/16 less thick and tapered from 1 3/4” wide at the Nut to 2 1/8” wide at the Twelfth Fret. The Fingerboard also gets a radius on the top side, fret slots, frets and position markers. Once the components are together the neck still needs to carved.
Carving the neck shape is for me the last step before gluing the neck to the body. There are several profiles used in carving guitar necks which have letter names according to their shapes, as in D C U then Oval. I carve mine to a C shape. The tools used to carve the neck are: chisel, small hand planer, rasp, spoke shave, and various files. I begin by carving the heel, then the headstock transition, and finish by blending the rest of the neck. It also requires a lot of patience to get it right. Once done though it’s very rewarding and takes us to the final component of Necking, the Nut.
The Nut is one of the most important components of the guitar and Necking. The overall best material for the job is bone. (Necking , Bone , Nut, ha… .) Poor choice of material and / or improper nut construction will result in poor tone and can cause high action, fret buzz, or tuning and intonation problems. The nut is shaped to fit into a slot at the base of the fingerboard, curved to the fingerboard radius and slotted to size for each particular string.
With the Nut in place and the neck glued to the body it’s finally time to locate and install the Bridge which will be covered next post. So, always remember when Necking it is important have a good Joint, Easy Fingering, Shapely Headstock, Hard Bone and a well done Nut.