Apart from the obvious appeal of making another electric guitar, Khaya was a concept study in producing a digitally designed and largely automatically fabricated object of high precision. The first step in this process was to know the facts, what I could do and what I could not. To fully comprehend the limits of the guitar all the components were modelled in 3D to less than a mm accuracy. The components were thereafter assembled digitally as if built in physical space. This step was crucial for determining factors such as angles, thicknesses and cut sizes. The most notable ones were the angle in which to attach the neck to the body and the depth of the cutouts for the pick-ups and the potentiometers. If the cutouts were too shallow, it would be hard to attach the components later, and too deep would mean a structural weakness. Once this was produced in the CNC mill and I had moved far enough with the post process to the point of actually testing these things, it would be very hard to go back and redo.

Although the guitar is more or less a copy of a Gibson Les Paul, I still wanted to personalize it to my liking through some minor tweaks, such as moving the volume control into my preferred location and designing the cutouts in the back to my liking. This was also made possible through this three dimensional visualization process.

Now, apart from visualizing these features, the three dimensional model holds a lot of information, a lot more than two dimensional drawings. I could extract tool paths for the CNC mill more or less directly from the 3D file. The automated production was split in two parts, one set of operations for the back side and another set for the front side.

The tricky part of this step was to translate as much precision from the theoretical world in which the guitar was designed, to the physical world in which it would be made.

My biggest concern was to align the set of operations on the back side with the set of operations on the front. I decided to drill four holes, one in each corner to lock the block in the y-directions and a fifth hole along a long side to lock it in the x-direction.

Ultimately, the method turned out successful and I only made minor changes to the three dimensional file before cutting proceeding to cut the actual stock material of mahogany.

Although not important to my study in digital fabrication, one cannot build a guitar without carefully reading up on various woods and their qualities.

After careful consideration I bought myself a piece of Mahogany from Honduras. Mahogany is a rather broad new for wood, but it is believed that the Mahogany stemming from Central America should have a warmer tone in terms of music. Central American Mahogany is furthermore a bit lighter, both in terms of color and in weight.

A very important aspect of digital fabrication is to map the digital world to the physical. In other words, where in the physical world exists the digital coordinate system?

To ensure accuracy in the process, 5 1/4" holes where drilled into the wooden piece. The 4 holes in the corners locked the wood into its Y-direction while also attaching it to the bed. The fifth hole was used to place the wood in the X-direction.

The entire operation for the back side of the guitar is finished. At this point the stock material is to be unscrewed and flipped around in its exact position.

The process of the front is here well under way. This is one of the last steps - a finishing pass over the front that gives the body it's nicely curved shape.

Wood coming right out of the CNC milling machine. At this stage, the body is attached to the stock material through only a thin layer. This is done so that the body won't come loose during the operation in the CNC milling machine. If the body would come loose, it would be hard to reattach it again and the drill would inflict irreparable damage on the wood.

After a careful but quick operation with the band saw, the body is freed from the stock material.

Before sanding down the body. The surface needs finishing, but the curve shape of the body is on point.

Another crucial part of making the guitar is the alignment of all components. This can be a lot more difficult than first expected. However, thanks to the precision of the CNC milling machine it can be relatively easy. This is how well my neck aligned with the stable after a quick sanding process.

The head of the guitar was rather difficult. It was easy to fall into the trap of just reproducing a Les Paul head, but I wanted to push it further. This became my very minimalist approach to the top of the head.

Once cut out, it was time for the paint job. A few lessons from this process is patience, quality paint and buy the right type of sand paper.

After removing the tape and attaching the components, this was the final outcome.

Before taking any steps in terms of coating the guitar, it needed to be sanded to a fine surface. Although wood can only get so fine of a surface, it is still very important to take this part of the process seriously as any bumps will be amplified by the coat rather than covered up.

Mahogany is rather porous as a wood. Therefore it needed a grain filler before the lacquering process would begin. I used a slightly tinted grain filler for this model. At this stage, when the grain filler is just applied, it looks like it has made a significant alteration to the color of the wood.

However, when the guitar is sanded and only smaller parts of the grain filler remains, it really didn't change the color significantly. It did however make the surface of the wood incredibly smooth which in turn made the lacquering process far easier than expected.

Before putting down any layer of lacquer, the wood was stained to gain a little bit more tone. I personally prefer a darker wood for my guitars and this got the wood where I liked it. It is also worth pointing out that it has grown slightly darker since I first stained it.

After the staining was completed, two base layers of sanding sealer was applied. The sanding sealer is a type of lacquer that is relatively easy to work with, as the name implies. It can to some extent even out smaller uneven parts of a surface. Once a satisfactory result was achieved with the sanding sealer, nine thin layers of was applied.

Lacquer is an interesting coating material as every layer is thin, and each applied layer "melts" and blends with the previous. Therefore, lacquer becomes a unified, thin surface.

It is also worth mentioning that before proceeding to the next step. it is very important to properly finish each step before proceeding to the next as it is very hard to go back through the steps.

After the last layer of lacquer and after all the components were attached, this is what the guitar finally looked like.