R12.7 rounding cutter with guide bearing

Brief description

The R12.7 rounding bit rounds off wood edges with a 12.7-mm radius—the largest radius in this series—for generously rounded edges and a quarter-round profile. The ball bearing (Ø 12.7 mm) on the cutter head runs along the edge of the workpiece and guides the cutter even along curved contours where no stop fits. This allows you to round off straight edges as well as curved tabletops, handrails, or handle strips.

The cutter is double-edged and carbide-tipped (HW), right-hand cutting, with an outer diameter of 38 mm and a working length of 19 mm. Its 8 mm shank fits in hand routers, bench routers, and the RUWI router table (8 mm collet) as well as on CNC machines. It cuts softwood, hardwood, and laminated panels. If the ball bearing wears out, you can replace it—instead of replacing the entire router bit.

With a diameter of 38 mm, this router bit is designed for use in a router table and should be run at a reduced speed—which is a must, not an option, for this diameter. You can find more router bits in the RUWI router bit selection, and the matching tables in the RUWI router table selection.

Possible applications

• Round edges with a 12.7-mm radius—the largest radius in the series, also available as a quarter-round
• Milling curved contours without a stop—the guide bearing follows the edge
• Rounded edges on tabletops, handrails, grab bars, and stair treads
• Double-edged carbide end mill, right-hand cut, outer diameter 38 mm, effective length 19 mm
• Shaft diameter 8 mm for hand-held routers, RUWI router tables, and CNC machines – for large diameters in the router table, use a reduced speed
• For softwood, hardwood, and laminated panels
• Replaceable thrust ball bearing (12.7 mm diameter)

Downloads

RUWI Product Catalog 2026 (PDF)

All the details

- Profile & cutting
- Rounding radius R12.7
- Double-edged (Z2)

- Dimensions & design
- Shank Ø 8 mm | Shank length: 32 mm
- Useful/working length: 19 mm
- Overall length: 66 mm | Outer diameter: Ø 38 mm
- Weight: approx. 73 g

- Bearing & rotation
- Ball bearing Ø 12.7 mm
- Clockwise rotation

- material
- Carbide (HW)

- Application & compatibility
- For softwood, hardwood and coated boards
- Suitable for RUWI router tables (S/M/L), hand routers, router tables and CNC machines