3.5″ wide. 3 blocks. Your choice of radii.

A set of three radius sanding blocks for setting fretboard profile during a new build, restoring the radius during a refret, or leveling frets to the board's existing curve. 3.5″ width fits extended-range guitars (7-9 string) and basses (5-7 string).

Radius & Length

Lengths

• 4″ for spot work
• 8″ and 10″ for general fretboard sanding

Radii

• Imperial: 7.25″–30″
• Metric: 390mm–430mm
• Flat
• Custom: email us for a radius we don't list, no extra charge

Sandpaper

3.5″ wide adhesive-backed sandpaper isn't a standard size. Two ways to handle it:

• Trim a wider PSA roll. 4-1/2″ rolls cut down to 3.5″ with scissors or a straightedge and utility knife. Klingspor's 4″ roll category covers most grits.
• Use standard sheet sandpaper. Cut to size and attach with double-sided tape or a light coat of spray adhesive.

Material

3D-printed in PLA. Reasoning is in Why We Use PLA. Covered by our lifetime warranty if any block ever fails.

Working on a full build?

The Fretboard Radius Jig establishes the radius with a router in under ten minutes. The blocks then smooth the board after, a couple of minutes per grit. Many builders run both: jig for stock removal, blocks for finishing.

Want different quantities or a single block?

Buy single blocks at Radius Sanding Block (3.5″ Wide).

Specs