Cutting your fret slots
Cutting your fret slots is done before fixing your fretboard on your neck. After this, you have the option to work on a fixed fretboard or complete the fretboard and glue it on your neck at a later stage.
Prepare the Fretboard
Make sure that your fretboard has a straight edge and that the underside is flat. The straight side helps you to keep your ruler straight for accurate measurements and to make sure that you will saw each fret aligned and at a 90 degrees angle from the side. Fanned frets can also be an option, more about that at the bottom.
Position of the Nut
Cut the top of your fretboard at a 90-degree angle from the side straight through. This is the top of your fretboard. If your nut will be placed against the top of your fretboard, you can determine your scale, get your ruler and start marking positions. If your nut is slotted into your fretboard, than mark the our lines of your nut and saw both sides to the required depth. Remove the inner part with a micro chisel or small file and ensure that the nut will sit flat and tight in this nut slot.
Scale
Determine the desired scale, this is the length of the upper part of your fretboard, where it touches the nut, to the bridge. Most bridges have adjustable saddles with which you can later adjust the intonation per string. This is mm’s though, not cm’s! With the scale you can calculate the fret positions with our fret calculator. Commonly used scales are:
Gibson: varies from 62.38, 62.55 & 62.87 cm and 64.26 cm for a long scale
Fender strat & tele: 64.77cm
Fender Jaguar: 60.96 cm
Fender Mustang & Duosonic: 57.15 cm
Martin standard: 64.36 cm
Martin short scale: 63.09 cm
PRS: 63.5 cm
Classical guitar short scale: 65 cm
Classic guitar long scale: 66 cm
Most used for basses is the Fender scale:
Long scale: 86.36 cm
Short scale 76.2 cm
I myself usually use 87 cm for my bass, just to show you can vary.
Mark fret positions
Take your ruler, preferably a 600 mm metal one and align it straight. Mark the frett positions on both sides of the ruler accurately. Always measure the distance from the nut to the fret and check the distance between the frets. I like to use an eyeleteer to mark the positions, because pencil is not always clearly visible on darker wood and you also have a starting point for your fret saw. Every next frett should be closer to the other with less space between the frets. If something looks odd, chances are that it is off and better check again. It’s true; measure twice… we know.
Sawing
Preferably use a Japanese saw. Because the saw works by pulling it backwards, you generally have more control over the saw and it rarely give splinters because little pressure is needed. Use a saw that makes a cut in the same thickness as the gripper of your fret. The standard is 0.5 mm for regular frets and 0.63 mm for replacement frets.
You can use a carpenter’s square to guide your fret saw (use the straight side of your fretboard). Start with the first fret slot. Place your saw on the marking and place the square against the blade. Pull the saw backwards, slide up again and pull backwards again. Repeat until you have a fret slot that is deep enough for your frets. Keep in mind that you still have to sand a radius and that you lose height on the sides of your fret slot. After the radius sanding, you can clean the sloths for the final fit.
If you have sawn too deep, you can fill any visible gaps at the sides after fretting with wood glue and saw dust. Glue your frets preferably with thin superglue such as ours from ZAP. In case of deeply sawn slots, always glue them in. That is better for the sound.
Fanned frets
For fanned frets, use a different scale on the highest and the lowest string (and with that, of course all the strings in between). Fanned frets are straight frets that stand at different angles like a fan. This can have an advantage for the ergonomics and possibly an advantage for the intonation. What is in any case a proven advantage is that the string tension is better tuned to the thickness of the string and that benefits the ease of play. The disadvantage is that you wear frets faster and that you should actually opt for stainless steel frets. It looks pretty cool anyway and it is an interesting idea. How do you proceed:
Double scale
Determine the desired scale for the highest (thinnest) string and that for the lowest (thickest) string. Make sure not to go too steep and that your bridge still fits on the body and that you have room to adjust your saddle. Also keep in mind that you will need a separate bridge for each string, unless you only make a very small fan. Frequently used scale for a 6 string guitar is 68.58 cm for the thinnest string and 64.77 cm for the thickest string. Calculate the fret positions for both sides of the fretboard with the fret calculator.
Sawing
Cut your fretboard into shape and place your ruler along the edge to mark your first series of positions and repeat at the other side for the other scale. It can be handy to connect the markings with a pencil so that you have a visual of your sawing line. You can now no longer use a square to guide your saw, but you can grab a reasonably flat block of wood with a right-angled side and clamp it against the line of your desired fret. Then saw as described above.