Dovetail Neck Joint
Source: Guitar Building Articles, The Guitar Neck
Tools & Materials Needed
Back Saw or Dovetail Saw
Stewmac Dovetail Template
Laminate Trim Router
Stewmac Dovetail Router Bit
Stewmac Dovetail Bit Guide
Chisel
Dovetail Neck Joint:
The Dovetail Guitar Neck Joint is by far the most popular guitar neck joint used in the modern guitar and in all guitars starting in the 1920′s, when C.F. Martin made it a standard in their production guitars.
Making the Joint:
While you can make this joint with a dovetail saw or a Japanese Pull Saw. The biggest problem, especially for the beginning luthier is getting the correct cutting angles on both the male and female portions of the joint. If you cut it by hand it takes quite a bit of control and a lot of accuracy.
Most shops will either develop there own router and template method to get consistent results. With a carbide tipped dovetail router bit and either a full-sized router or my preference is the smaller one-handed laminate cut-off router.
Pre-Made Templates:
When I use a Dovetail Joint (and that is not that often), I have decided to use the Acoustic Neck Joint Routing Templates offered by Stewart MacDonald. They are highly accurate, durable and provide an exact set of matching joints for your guitar. Would also recommend the purchase of their special Dovetail Router Bit and Guide Bearing that was designed to be used with their template system.
StewMac Dovetail Template
Source: Guitar Building Articles, The Guitar neck
How to Use the Template:
You start by making a simple jig to hold both the neck and the body in a preset location. They include the directions for make this jig along with the template. Once the template in made you need to prepare the neck to fit into the jig.
When the jig is completed, mark a center-line on its top and upright. Be sure this aligns with the center of the templates. The center-line is helpful in positioning the body or neck when clamping it in the jig.
The jig holds the neck or body at a 90-degree angle to the cutter bit. When the guitar body is clamped onto the jig, with the soundboard against the jig’s upright, the mortise in the body’s head block can be cut properly at a 90-degree angle to the soundboard.
With the proper template in the top of the jig, adjust the router bit height. When using the cutter bit, there should be a gap between the template and the neck or body, to ensure proper contact of the bearing against the template, and the correct depth of cut.
It may be necessary to use two pieces of Teflon® tubing on the cutter bit, one above and one below the guide bearing. The neck tenon is usually 5/8″ long, and the body mortise is generally 3/4″ deep, leaving a 1/8″ gap between the end of the tenon and the bottom of the mortise joint. This gap is useful for final fitting and for steaming the neck loose if future re-setting should become necessary.
Note: If you decide to make your neck with a slight angle to the top and sides of the guitar, a shim should be placed between the neck and the face of the jig’s upright, to hold the neck at this angle before clamping it to the jig.
Tags: dovetail neck joint, dovetail router template, how to make a guitar neck, router bits, stewart macdonald, stewmac
