R8 rounding cutter with guide bearing

Brief description

The R8 rounding bit rounds off wood edges with an 8-mm radius—a large radius for generously rounded, easy-to-grip edges. The ball bearing (Ø 12.7 mm) on the bit head runs along the edge of the workpiece and guides the bit even along curved contours for which no stop fits. This allows you to round off straight edges as well as curved tabletops or handrails.

The cutter is double-edged and carbide-tipped (HW), right-hand cutting, with an outer diameter of 29 mm and a cutting length of 13 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, MDF, and laminated panels. If the ball bearing wears out, you can replace it—instead of replacing the entire router bit.

For large radii and the 29 mm head, it’s worth using a router table—it runs more smoothly and safely than freehand. You can find more router bits in the RUWI router bits section, and the matching tables in the RUWI router tables section.

Possible applications

• Rounding edges with an 8-mm radius – on straight and curved workpieces
• Milling curved contours without a stop—the guide bearing follows the edge
• Roughly round off furniture edges, tabletops, stair treads, and handrails
• Double-edged carbide end mill, right-hand cut, outer diameter 29 mm, effective length 13 mm
• Shaft Ø 8 mm for hand-held router, RUWI router table, and CNC
• For softwood, hardwood, MDF, and laminated panels
• Replaceable thrust ball bearing (12.7 mm diameter)

Downloads

RUWI Product Catalog 2026 (PDF)

All the details

- Profile & cutting
- Rounding radius R8
- Double-edged (Z2)

- Dimensions & design
- Shank Ø 8 mm | Shank length: 32 mm
- Useful/working length: 13 mm
- Overall length: 59 mm | Outer diameter: Ø 29 mm
- Weight: approx. 42 g

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

- material
- Carbide (HW)

- Application & compatibility
- Ideal for softwood, hardwood and coated boards
- Compatible with RUWI routing tables, hand and table routers and CNC machines