The Benchmark Abrasives SL-4NF aluma cut taper shape radius premium tungsten carbide burr is built for fabricators, machinists, welders, and metalworkers who need controlled material removal on aluminum and other soft nonferrous materials. Unlike lower quality burrs that may use hollow heads or inconsistent brazing, Benchmark carbide burrs feature a solid carbide head with a silver-brazed connection to the shank. The result is a strong, stable cutting tool made for demanding deburring, shaping, contouring, and material-removal applications.
The SL-4NF combines that premium construction with a large 1/2" taper profile, a rounded radius end, and Aluma Cut tooth geometry. Its gradually narrowing shape is well suited for tapered contours, rounded transitions, recessed features, and applications where the cutting width needs to change progressively along the surface. The wider, more open tooth spacing provides chip clearance on aluminum and other soft nonferrous materials to help reduce chip packing during cutting.
Whether you're shaping larger tapered aluminum contours, blending broad rounded transitions, refining recessed features, or removing material through progressively changing surfaces, the SL-4NF provides more cutting area than the smaller SL-3NF while retaining the same radius-end control. The 1/4" shank fits compatible die grinders and rotary tools with a matching collet, while the standard-length 1/2" head is rated for a maximum speed of 50,000 RPM.
Features
- Premium tungsten carbide construction
- Aluma Cut tooth geometry for improved chip clearance
- Open tooth spacing suited for aluminum and soft nonferrous materials
- Large tapered profile for progressively changing contours
- Radius end for smoother rounded transitions
- 1/2" maximum head diameter for broader cutting contact
- 1-1/8" cutting length for extended contour engagement
- Suitable for deburring, shaping, blending, and medium stock removal
- 1/4" shank for compatible die grinders
- Sold individually
Applications
The SL-4NF taper radius-end profile is well suited for:
- Tapered contours
- Rounded transitions
- Recessed shaping
- Internal contour refinement
- Deburring aluminum parts
- Blending changing surface widths
- Medium localized stock removal
- General nonferrous fabrication and maintenance work
Materials
The Aluma Cut tooth pattern is intended primarily for:
- Aluminum
- Other soft nonferrous materials
Its wider, more open tooth spacing is designed to provide chip clearance on softer materials where closely spaced cutting teeth can be more prone to loading.
Machine Compatibility
Designed for die grinders and other rotary tools equipped with a properly sized 1/4" collet.
Compatible examples include:
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Benchmark Straight Pneumatic Die Grinder (BMT-DGST_1) — 1/4" collet, up to 25,000 RPM.
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DEWALT DCG426B — 1/4" collet, variable speed up to 25,000 RPM.
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Milwaukee 3485-20 — 1/4" collet, variable speed up to 20,000 RPM.
Always confirm the burr shank is securely seated in the correct collet and that the machine speed is appropriate for the burr diameter, workpiece material, and application.
Cutting Performance
The SL-4NF uses a larger tapered cutting profile that gradually narrows toward a rounded radius end. This geometry is useful when the workpiece contour changes width or depth, allowing different portions of the burr to engage the surface as needed while blending through rounded transitions more smoothly than a pointed taper.
Its 1/2" maximum head diameter and 1-1/8" cutting length provide more cutting area than the SL-3NF, making it better suited for broader contours and medium stock removal. The Aluma Cut tooth pattern uses wider, more open spacing than a double-cut burr, providing additional room for chips to clear during cutting on aluminum and other soft nonferrous materials.
Carbide burrs are primarily cutting and shaping tools; applications requiring a refined cosmetic finish should be followed with the appropriate abrasive finishing process.
Use the aluminum row in the 1/2" chart as suggested starting guidance. Conventional die grinders commonly operate at 20,000–29,000 RPM; adjust within your machine’s range for smooth cutting. The other material rows are general burr references, not recommend
Do not exceed the 50,000 RPM maximum speed for this standard-length 1/2" carbide burr. Always operate within the lower maximum speed of the burr, machine, collet, or accessory system.
Safety Tips
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- Secure the workpiece before beginning operation.
- Confirm the 1/4" shank is properly seated and securely tightened in the correct collet.
- Use light, controlled pressure and allow the carbide cutting edges to remove the material.
- Keep the burr moving during cutting rather than holding it stationary against the workpiece.
- Maintain control when working through tapered or recessed contours.
- Avoid excessive force, which can increase heat, vibration, and premature cutting-edge wear.
- Select operating speed according to burr diameter, workpiece material, machine requirements, and the recommended operating-speed chart.
- Never exceed 50,000 RPM.
- Stop immediately if excessive vibration, chatter, unusual noise, or visible damage occurs.
- Do not use a damaged, chipped, bent, or improperly mounted carbide burr.
