Onsrud 57-320 Downcut Spiral Router Bit 3/8 in Solid Carbide

Product Description

The ONSRUD 57-320 is a downcut spiral router bit designed for clean, controlled cutting in natural wood, solid surfaces, and wood composites. Built from solid carbide with a double-edge flute configuration, it runs at a 30-degree helix angle with right-hand cutting direction. The 3/8-inch cutter diameter paired with a 1.125-inch length of cut makes it well-suited for routing operations where surface finish on the top face is the priority. Downcut geometry pushes chips downward, reducing tearout and fraying on the workpiece surface. Licensed machinists and CNC router operators are the primary users of this bit type.

This bit fits applications in woodworking shops, cabinet fabrication, and composite panel processing. Typical uses include dado cuts, edge profiling, and pocket routing in natural wood panels, MDF, plywood, and solid surface materials. The 3/8-inch shank seats securely in standard collet systems. The 1.875-inch shank length provides adequate engagement in most CNC and handheld router setups. It is part of the ONSRUD 57-200 series, which targets production and professional-grade routing in non-metallic materials.

Key Features

• Downcut flute geometry reduces surface tearout on the top face of the workpiece
• Solid carbide construction for durability and edge retention in abrasive composites
• Double-edge design improves feed rate capability and cut quality
• 30-degree helix angle balances chip evacuation and cutting stability
• Right-hand cutting direction compatible with standard router spindle rotation
• Uncoated finish suitable for natural wood and solid surface applications

Compatibility

Designed for use in natural wood, solid surfaces, and wood composites. Compatible with routers and CNC spindles accepting a 3/8-inch collet or collet reducer. Part of the ONSRUD 57-200 series.

Installation Notes

Installation is performed by machinists or CNC router operators. Power down and de-energize the spindle fully before inserting or removing the bit. Seat the shank to the full recommended collet engagement depth and tighten the collet nut to the router or spindle manufacturer specifications. Inspect the cutting edges and shank for chips or wear before each use, and do not operate a damaged bit.