Making an Electric Guitar Body

Introduction

Last year I built a 3D router ¹ ² ³ to serve as a manual CNC machine, after seeing it in full flight in the video. It looked perfectly simple, and after building it, it has taken a while to sort out my systems for actually using it. But I figure; spending time getting the templates sorted, and everything perfect, will allow for unending repeatability of creating 'perfect' electric guitar bodies.

How it all works

Firstly, I have made two boards; one for the template and one for the wood/guitar body. The guitar body has already been roughly cut out using a jigsaw or bandsaw at this stage.

Attaching the template

The back of the template board has 4 locations for attachment screws which fit close the edges of any guitar shape, regardless of whether they are for the front or the back of the guitar. Each body shape (front and back) are colour outlined to ensure that the mount points are within the body, and are not going to be in any template holes. Using screws, the template is then attached to the board from the back. This was initially a bit difficult, so I used double sided tape to hold the template in the right place while I used screws from the back to secure it. Next time, I should just be able to screw straight into the existing holes made in the template. The same process was carried out for attaching the body. The back of the body board is a bit more complicated, in that the mount screws have to go into places that are not going to be in lasting places on the guitar. To avoid this, the screws attach in places like the back vibrato spring cavity (for Stratocasters) and uses the same holes for the faceplate screws, or the string through-holes (for Telecasters). I've also used places for the elbow cutaway on a Stratocaster front to allow for attachment to drill out the back cavities.

Choosing the pickup setup

Each template I have made with a square hole to fit in different arrangements of pickups. This will allow me to fit any pickup arrangement to any body type, without having to re-make loads and loads of body templates; just the square cards for different pickup setups.

Loading Up

Putting the boards onto the table is a relatively straight-forward exercise. Both boards are 350mm wide. They slot together front and back on the table and align to each other. Threaded inserts in the table allow the boards to be bolted down in the same place each time. This is very important for repeatability. In addition to this, the distance from the router bit to the follower guide/bearing is exactly (or very near to) 350mm, and are aligned centre to centre as well. This means that if the follower is in the bottom left corner of the template board, then the router bit is in the bottom left corner of the master/body board. As the follower guide bearing traces around the template, the router bit carves out the shape on the body.

Follower Guide

The follower bearing is then selected to match the size of the router bit. I have made a series of bearings that match the different sized router bits that I have. Small router bits are used for getting into tight curves, while larger router bits are good for taking out larger chunks of the guitars.

The follower bearing is screwed into the back of the follower, and then this is lowered into the template for the interior cuts, or lowered around the outside for tidying up the edge of the body, which is still in it's rough cut stage at this stage.

Ready to Start

As you can see in the final photo, you can see that the follower bearing is in place to go around the pickup cavity of the template. The router bit is ready to mimic this and cut into the body.

The True Benefits

The true benefit of this system is repeatability. It allows me to create any number of combinations for various guitar setups, and replicate each one with a high degree of accuracy. But even more than this, it keeps the router bit well away from the templates themselves. Before now, I had used template cutters, which are router bits with a bearing around the top of the shaft that follows the template while the cutter cuts away at the wood. This is find for the edges of the body, but when it comes time to do the pickup cavities, there is no depth for the bit to go into, and so for the first half inch, the router cannot follow the bearing, as the bearing has nothing to roll against (unless your template is an inch tall!). Subsequently, many of my initial templates have received dings and nicks from minor slips of the router, and are no longer accurate. This system completely does away with that, because the bearing, instead of being on the router bit, is a good distance away from the cutting edge, and in turn, so is the template. Keeping the template in perfect condition is important. Any nicks or bumps, dings or scratches on the template are directly transmitted onto each body that is run through that template. This is also part of the reason why I have spent so long making sure that my templates are as close to perfect as I can get them before beginning to use them on my guitars.