Prior to shaping the guitar neck, make sure you have completed the following construction and assembly steps – note that this is considering a bolt-on neck installation or a dovetail neck installation for the acoustic guitar. Note this article also applies to ukulele neck and electric guitar necks.
Steps Completed on the Acoustic Guitar:
- The body of the guitar is all glued up, purfling and binding installed and shaped.
- The guitar body is finish sanded with 220 grit sand paper
- The fretboard has been mounted.
Tools and Materials:
Surform Shaping Tool
Surform Hand Shaper
6″ 4-Way Shoe Rasp File
Digital Vernier Calipers
If this is your first acoustic or classical guitar, I would recommend that you hand shape the neck by taking small amounts of stock away from the neck and checking the shape and curvature often with neck contour templates.
To rough out the neck, I would recommend a few different tools. One of my favorites is the 6″ 4-Way Shoe Rasp File. This is a 6″ tool with curved and flat rasp and coarse file faces. The rasp allow hogging out of a lot a materials and the file allows for fine-tuning.
Check the thickness of the neck with a Digital Vernier Calipers often. One of the more critical things to check is the flatness and consistency of the neck taper on the underside of the neck from the nut to the base of the heel. This should be a very straight line, even though it is tapered.
Neck Contour Templates:
One of the best ways to get the neck shaped accurately is to make a couple of neck shape or neck contour templates. You should make one for the neck cross-section at the first fret 6th fret and the 10th Frett (or the highest fret prior to the base of the heel for a 14 Fret Guitar). There are several ways get accurate contours for these templates.
1. You can design your own.
2. You can grab a contour from an existing guitar neck that you like, using a Contour Gage.
3. You can use a starter template from the plans from Georgia Luthier Supply or download our free acoustic guitar neck templates.
Once you have the contour drawing, paste it on a piece of plastic, plexiglass or thin solid wood, and cut it out using a sharp knife or a band sand and sanding it carefully by and or with a stationary drum sander.
Shaping The Neck:
To hog off the most wood, I use a Surform Shaping Tool. This tool will take down an amazing amount of wood in a short period of time.
Once I have the neck shaped to within about 1/16″ to 1/8″ (2 – 3 mm) of it’s final shape, I switch over to the 6″ 4-Way Shoe Rasp File and smooth the neck with the different cutting faces. This tool is great because it has both flat and curved faces that let you address the many facets of the guitar neck.
To shape the guitar heel, I use the Surform Hand Shaper. This is a more contoured tool and you can get in around the curves of the heel much better.
Again, I switch over to the 6″ 4-Way Shoe Rasp File to get down to the final shaping.