Large Factory Production. Larger factories can usually produce between 8000 to 15000 guitars per month and usually have much more automation in the line. This save costs in hand work as well as keeping the production very consistent. One problem with this, one mistake with a machine and chances are many guitars could have the same problems. Basically the production starts the same way as any factory, they need to have orders so they can prepare the materials that will need to be ordered for production. This is everything from woods to electronics. After the supplies are in stock the guitars are ready to be produced, here is a basic production process.

The woods are stocked and dried to the proper moisture content depending on the type of wood and the time of year that the guitar will be produced. Before production begins, large factories buy the woods usually in either logs or board feet by the container. To get the best yield the logs are used for any number of parts on the body or neck. An example would be a guitar that has a mahogany body as well as a mahogany neck. The woods are first sorted, cut to size, planed to the correct thickness and placed in a drying room to sit for a few days until the moisture content is stable.

After the woods are joined and planed to the correct size, massive CNC machines that usually have between eighth to twelve heads are used for rough shaping the bodies and necks. The CNC usually uses two heads per piece, this way they don't need to change the tools during the machining. A ten head machine can make five bodies or necks at the same time. One head will cut out the bodies shape, neck pocket, tremolo routs and pickup routs and the other head will come down and do the round over. The same with a neck, the first head will shape the neck and the second head does the round over on the back. Run time on these machines is generally between two to five minutes per side. You can figure that a CNC with ten heads is capable of making five bodies every eight minutes. If you do the math this is roughly 300 bodies per day or 7200 bodies per month in just 24 eight hour days. Watch A Video Video Part II

These machines can usually be operated by one person, each machine has two large tables so while the CNC is working on one table they are unloading and loading the other table. To attach the wood to the table, location holes are drilled for use with set pins mounted on the tables. This is used for lining up the wood when it is flipped over so the CNC can rout and shape both sides. The basic profile of the part is outlined on the table so the wood blanks can be lined up and locked in place using vacuum. Watch a Video

On models that are through necks the production is still mainly by hand because of the construction techniques. For these models , they are basically roughed out on a band saw and then a pin router is used to do the final body shape. For a round over on this type of body they sometimes use special round over cutters on pin routers that shape the entire round over at one time. Watch a Video

After the bodies are rough cut on the CNC they are moved to the sanding section where the comfort cut is added and any imperfection or tear out is removed. For the comfort cuts on the top and back they usually use a slanted jig on a band saw but recently I have seen a machine that is kind of a "merry go round" that slices the top and back as it passes the saw blades. This machine is quite expensive but a big time and labor saver. Watch a Video

After the CNC rough shapes the necks, they still need allot of hand work. First they are moved to an area where the headstock and heel areas are shaped and the truss rod slots are cut. For a standard skunk stripe neck, the channel would be routed from the back and a vertical drill press is used to drill the truss rod bullet under the nut area. With standard truss rods the neck is routed before the fretboard is installed.

After the truss rod channel is routed the fretboard's are installed, if there is any inlay work or position markers this is done in the fretboard before it is glued on. Position markers are drilled with a multiple press, they have a different press for each scale length as well as ones for basses The necks are now final shaped and sanded to there specific shapes and prepared for stain and sanding sealer before finish.

If there is any binding, the channels are routed on a router table and the binding is installed using a duco cement and masking tape. On areas that are bound such as the headstock, the binding is pre shaped in small presses that are the shape of the headstock and then they are installed, this saves the time of bending the exact shape for each headstock. Watch a Video

For bodies or necks that are stained, the parts are moved to a separate area and a urethane based wood stain is applied to the bare wood. If there is any bursting to be done it is done after the first stain coats are applied and the sanding sealer is cleared over the stain. Sanding sealer is used to seal the grain so that a finish can be applied evenly without sinking. Sanding sealer formulas throughout the world are different. Most Japanese companies use straight polyester while most of the Korean or Chinese factories use a 50/50 mixture of Polyester and Polyurethane. The reason is that the Japanese factories have better climate control in the factories and Polyester should be sprayed at approx 70 degrees or the formula needs to be modified so that it will dry. In Korea the factories are less climate controlled so the Polyurethane insures that the polyester will dry. The larger factories use static paint systems for this process. Watch a Video Static paint works this way, it uses a positive an negative charge. The body moves around slowly on a chain and as it passes the paint head, finish is sprayed in the air and it is pulled to the body like a magnet. The line constantly moves and the bodies and necks are added or removed from the line. After the sanding sealer is applied the bodies and necks are sent to a heated drying room where they will sit for approx three days until the sealer is dry. From there the necks are sent to the fretting department and the bodies are moved to a sanding area to prepare them for paint.

For the necks the fretboard radius is cut using either on a shaper table or a special machine that is designed to use a radiused cutter that passes over the fretboard radiusing it. Most factories still use a standard shaper table and a radiused cutter. Watch a Video

For the final sanding of the fretboard before fretting they use a 3 belt multiple press, the fretboard radius is milled into the stainless steel block along with a small amount of relief in the center of the mold. The neck moves automatically from one belt to the other starting at about 80 and finally ending at 400. The amount of times that the belt is lowered to the fretboard can be changed to any number of passes, Also if the radius is different the stainless mold can be changed.Watch a Video

For fretting the wire comes in large rolls and they have a machine that first straightens the wire and then cuts it to the exact length for each fret. If there is binding the frets ends are cut back on this machine.

For fretting the frets are first hammered in by hand, just to set them and then the frets are pressed in using an arbor press. The next step is the sides are sanded back to a 45 degree angle using a belt sander and an angled table. The frets are then leveled and dressed by hand. Watch a Video

When the finish is dry the bodies are moved on carts to the sanding area where they are prepared for the final finish. The top and backs are sanded on a stroke sander with between 320 and 400, and the sides are sanded on the end drum of a belt sander. Just before finishing, the bodies are roughed up with Scotch pads to make sure that the surface is ready for finish. After the bodies are sanded and prepared for finish they are sent to the paint area for color spraying. Depending on the factory the color spraying system is different. Most factories still use standard spray guns to apply the color coats and all metallic colors are also sprayed through standard paint guns.

In Japan many of the solid colors like red, black and white can be added directly to the Polyester and used as a static paint that can be applied using the static paint system. This system applies the color and the finish at the same time. Certain colors in the factory require different spraying techniques, on many colors the bodies are first painted a base coat and when a second or third color is applied the final color is made. Usually to brighten up a color they would use a white base coat and on some darker colors a black base coat may be used. Metallic colors usually have the flake added into the paint at the factory before spraying so that when the paint is applied the metallic is applied at the same time. Larger colored flakes and certain pearl finishes are added to a clear and applied over the color, this adds more dimension to the finish. After the finish is applied, the bodies are hung on racks and again moved to a heated drying area for 24 hours before they are cleared with a top coat. Most top coats are either polyester or the 50/50 polyester/ polyurethane mixture and applied with the static paint system. The drying time for each factory is different depending on the formula of finish and the factories production but drying of the final finish is usually in the drying room for between one to three days. The longer the drying time the harder the finish is and this allows a better shine because the sanding scratches are not as deep on a harder finish.

Once the finish is dry it is moved to the sanding and buffing section where the clear is first sanded on a stroke sander with #400 paper and then the body moves through a wet sanding area where the body is completely wet sanded to 1000 by hand before buffing. Watch a Video

When the bodies are completely wet sanded to #1000 they are first buffed on a buffing machine, using a liquid compound that is brushed on the top and back. The table moves back and forth and side by side. This machine buffs the top and back and the final buffing of the sides is finished on a buffing wheel by hand. Watch a Video

The guitar bodies are final polished by hand and and depending on the factory they could have the pickup and back plates routed at this point. The purpose of routing after the finish is so that the plates and pickups fit perfect without having extra paint and finish in the cavities. All open routs are sealed with a shielding paint that first seals the open wood and then shields the electronics. The bodies are then routed for the final pickups and tremolo routs, shielded and sent to the assembly area.

In the assembly area the parts are installed on the bodies and the electronics are wired up. The necks are also assembled and the tuning machines and any other hardware such as a top lock is installed. Once the bodies and necks are completed they are matched up for a perfect fit. If the neck is too tight the neck pocket can be sanded inside with a Dremel tool and a small sanding drum to make sure that there is a tight fit.

To install the bridge location they have jigs that start at the nut and follow the center line of the fretboard, The exact location of the studs or screws are marked in the body and the bridge is installed at that location. This is so exact that the intonation on the bridge can be pre-set at the manufacture and when the bridge is installed only a slight intonation adjustment may be needed. Watch a Video