TOOL
Fret slotting saw
One saw, one kerf, no second chances.
| Kerf | 0.020 – 0.024 in, matched to the tang |
|---|---|
| Tooth count | 20 – 24 teeth per inch |
| Plate thickness | 0.020 in typical |
| Depth stop | Fitted or adjustable, 1.5 – 3 mm |
| Handle | Wood or composite, two-hand or pistol grip |
| Set | Minimal — a wide set makes a loose slot |
| Slot depth | Tang depth + 0.5 mm |
|---|---|
| Slot position tolerance | ±0.05 mm |
| Cutting action | Pull stroke, light pressure, let the teeth work |
| Life | Hundreds of slots before sharpening |
| Guide | A mitre box or a slotted template improves consistency |
| Price band | Moderate |
A fret slotting saw is a fine-toothed saw with a kerf matched to the fret tang — typically 0.023 in. It cuts the slots that hold the frets, and the accuracy of those slots is the accuracy of the instrument’s intonation.
Most have a depth stop or a backing plate so the slot cannot go deeper than the tang plus clearance. A saw without a depth stop is a saw that will eventually cut through the fretboard.
At this stage
Slot position is calculated from the scale length, not measured by eye. Lay out from a template or a ruler stop and check the twelfth fret lands at the midpoint.
Suits these instruments
- All fretted instruments
Works with
- Ebony or rosewood fretboard
- Fret wire
- Notched straightedge
- Mitre box
- A slotting saw has a very thin, unsupported plate. It snaps rather than bends — do not force it or lever it sideways in the kerf.
- Secure the fretboard in a vice with a backing board so it cannot shift mid-cut.
Working notes
- Cut every slot in one direction, using the same reference edge, so any error is consistent.
- Check the depth on every slot. A shallow slot lifts the fret and ruins the level.
- A slotted template or mitre box costs more than the saw and saves more than it costs.
- Brush the saw clean between boards — packed dust widens the effective kerf.
Related
Fret wire
Nickel silver or stainless, and the crown shape decides the feel.
Fret press
Seats a fret evenly instead of hammering it in.
Fret leveling file
Makes every fret the same height, then gives the crown back.
Nut file set
The slot depth sets the action at the first fret.