Bolting on the neck

Saddles

Scale length mark

the intonation

Positioning the bridge

The exact position of the bridge should be determined after the neck has been fitted (7). Place a 1-meter (3-feet)-long rule along the neck so that it butts up against the front edge of the nut and mark the scale length on the body center line (8). If you don't have such a long rule you can either measure half the scale lenght up from the 12th fret or measure the difference of scale length minus the distance from the nut to the last fret up from the last fret. Then place the bridge on the body so that it is centered on the neck; the center is easy to find with one straight, narrow strip of wood placed on either side of the fingerboard. Set all the saddles on the bridge as far towards the fingerboard as possible and then move the entire bridge back or forward until the saddles are at the scale mark. Later, when you set the intonation, all the saddles are set back a little to make the vibrating length of the strings longer than the scale (9). This is necessary to compensate for the increase in pitch caused by pressing down the strings. Picture 7 shows a guitar with a rule on top of it and two strips of adhesive tape marking one end of the Telecaster's 25.5" (647.7mm) scale. Note that the bridge still needs to be moved back until the left saddle, which has been set as far to the front as possible, is exactly at the scale mark. When this position has been found hold down the bridge and mark the bridge mounting holes.

If the strings have to be passed through the body, mark and drill those holes as well. I'm convinced you will manage a more evenly-spaced layout and a straighter line than I have (10).

10

Bridges mounted on two posts

Bridges mounted on two posts are positioned slightly out of right angles to the fingerboard center line to get the best intonation adjustment options possible. If the guitar is to have a separate tailpiece, fit it about 50mm (2") behind the bridge. How deep you will have to drill and what hole diameter will be required depends on the height-adjustment bolt bushings of both the bridge and the tailpiece.

Determining the position of a bridge with seperate tailpiece

The exact position of the bridge can only be determined accurately after the action has been set correctly and strings of the same gauge as the ones that will eventually be used have been fitted.

When using a bridge with separate tailpiece it is not just possible but actually advisable to initially only fit the tailpiece and the tuners and to string the guitar. At this stage a rough-cut nut will do. By moving the bridge under the strings you can now find the correct intonation. Remember: whenever you change the action or put on a different string gauge, the bridge has to be repositioned; and every time the bridge position is changed the strings have to be retuned. Please refer to the set-up section for details. If due to the height adjustment posts the bridge is suspended, it has to be moved together with a suitable shim placed under it.

1

3

2

Fitting a headless unit

Headless guitar tuning units are often fitted to the body at a small downward angle. For this you need an angled surface which can be made with a template fastened accordingly (1). Then test-fit the unit (2), fastening the head part at the end of the neck with two screws (3). The allen key demonstrates that ordinary strings without second ball-end can also be used.

Bridges that can't be adjusted

If you have a bridge that doesn't allow string length adjustments, try a slanted saddle position as on an acoustic guitar. Move the saddle 3.81mm (0.15") back and then turn it slightly so that over a length of 7.62mm (3") the bass side is 3.2mm (1/8") further back than the treble side (as shown below):

3.2mm (1/8") 7.62mm (3")

Another approach would be to string up the guitar first and fasten the strings temporarily with an archtop guitar tailpiece fixed at the strap pin hole. Now try to find the best position for the bridge by moving it until the intonation is right. Remember to re-tune after each movement of the bridge. This adjustment is, however, only valid for the one string gauge and also only for new strings.

Fitting a tremolo

For installing a Strat-style tremolo you first have to cut out a 78mm x 16mm (3"x 5/8") elongated hole from the body. For measuring I always use the tremolo unit that will eventually be installed on the guitar. Unscrew the tremolo block from the bridge, place the bridge on the body as you would do with a normal bridge, trace its outline and mark the center line of the tremolo block to the left and right and also the position of the tremolo block. Then rough-drill a 78mm (3")-long hole with a 14mm (9/16") bit mounted in a drill press or in a stand-mounted power drill as in picture 4. I clamped two guide boards and a backing board to the body. After that make a routing template from four rectangular pieces of wood (5) by fastening them around the rough-drilled hole with double-stick tape. The two middle pieces are both 16mm (5/8") wide. Now clean up the elongated hole as deep as possible with a 19mm (3/4")-long flush-trimming cutter with shank-mounted ball bearing. After removing the template deepen the elongated hole, using the already-cut hole walls as a guide for the ball bearing to ride against. Remove anything that is still left after that with a chisel (6). Alternatively, you can also carefully pre-drill and then clean up the whole elongated hole in one pass with a 12mm (1/2")- diameter, 50mm (2")-long flush-trimming cutter with endmounted ball bearing in a table-mounted router.

Now mount the bridge plus tremolo unit on the body and mark a

elongated hole to about 24mm (15/16"). Then remove the template (8) and continue routing until the recess is

40mm (11/2") deep and only 5mm (1/4") of the body are left over a 16mm (5/8") wide area. Standard Strat-style tremolo units can only be fitted to bodies that are at least 45mm (13/4") thick.

Fasten the spring mounting claw at the front of the spring cavity by means of screws placed at a small angle of about 6 degrees. A long and thin drill bit is required for pre-drilling these screwholes. Alternatively, you can also use a 3mm (1/8") auger gimlet (9). To allow spring tension adjustment don't drive the screws in all the way (10). Remember also to drill a hole into the control cavity for the string-grounding wire.

Fit a cover plate over the spring cavity. The strings can be fitted by passing them through the six holes of the cover; the cover itself doesn't have to be removed for fitting the strings.

Routing for a

Strat-style tremolo

View from the back of the body

Spring cavity 57 x 100 (2 1/4 x 4)

16 (5/8) deep centered to the springs

Measurements in millimeters (in brackets: inches)

4

16mm

(

5/

8

")

wide

Pickguard and pickup

If you fit a pickguard on the body of your guitar, you can be far more generous as far as the size of the pickup cavity is concerned.

The Fender American Strat, for instance, has got just one single, rectangular and fairly wide, cavity that can hold all three pickups. This has one obvious advantage: it makes it possible to fit any pickup combination later by simply removing the pickguard and without having to cut any new cavities. Another advantage of a larger cavity is the slightly reduced weight of the guitar.

Because of the pickups being virtually suspended in the air the sound transmission is sometimes said to be less good with larger cavities than with pickups that are closely surrounded by wood. Whether or not this has an effect on the sound is not for me to decide.

Scale 1:1

20mm (13/16”)

8mm

(5/16”)

“Ears” can be routed deeper if necessary

20mm (13/16”) deep

71mm (2 13/16”)

40 (1 9/16”)

Cavity needed for humbucking pickup (grey area)

If you use a humbucker mounting ring, as shown in the drawing on the left, you can be far more generous with regard to the size of the pickup cavity. Obvious limitations are that the ring must cover the whole cavity and that there is still enough wood left in the corners for screwing down the mounting ring.