Product Specification
SD-51NF BALL SHAPE ALUMA CUT CARBIDE BURR – 1/8" SHANK
The Benchmark Abrasives SD-51NF ball shape premium tungsten carbide burr is built for fabricators, machinists, metalworkers, and detail-oriented users who need controlled cutting performance on aluminum and other soft nonferrous materials in tight or contoured areas. 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 designed for precise deburring, shaping, contouring, and localized material removal.
The SD-51NF combines that premium construction with a compact 1/4" ball head and Aluma Cut tooth geometry. Its spherical profile is well suited for concave surfaces, radiused cavities, rounded recesses, and free-form contouring, while the wider, more open tooth spacing provides improved chip clearance on aluminum and other soft nonferrous materials to help reduce chip packing during cutting.
Its 1/8" shank makes the SD-51NF well suited for compatible rotary tools and precision grinders equipped with the correct 1/8" collet or chuck. The compact ball head provides excellent access for detailed cavity and contour work, while the standard-length 1/4" head is rated for a maximum speed of 70,000 RPM.
Product Specifications
| Specification | Details |
|---|---|
| Product Code | SD-51NF |
| Burr Material | Tungsten Carbide |
| Head Shape | Ball |
| Cut | Aluma Cut |
| Head Diameter | 1/4" |
| Cut Length | 7/32" |
| Shank Diameter | 1/8" |
| Overall Length | 2" |
| Max RPM | 70,000 RPM |
| Quantity | 1 Piece |
Features
- Premium tungsten carbide construction
- Aluma Cut tooth geometry for improved chip clearance
- Open tooth spacing suited for aluminum and soft nonferrous materials
- Ball-shaped head for concave surfaces and radiused cavities
- Compact 1/4" head for detailed contouring and confined areas
- Rounded cutting profile for multi-angle surface engagement
- 1/8" shank for compatible rotary tools and precision grinders
- Suitable for deburring, shaping, contouring, and localized stock removal
- Sold individually
Applications
The SD-51NF ball profile is well suited for:
- Concave surfaces
- Radiused cavities
- Rounded recesses
- Internal contouring
- Curved-surface blending
- Deburring aluminum components
- Detailed cavity shaping
- 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 better chip clearance on softer materials where closely spaced cutting teeth can be more prone to loading.
Machine Compatibility
Designed for rotary tools, precision grinders, and other compatible machines equipped with a properly sized 1/8" collet or chuck.
Compatible examples include Dremel® 4300, 4000, and 3000 fitted with a Dremel 480 1/8" collet and matching collet nut. The 4300 can also hold the 1/8" shank in its keyless chuck.
Always confirm the 1/8" shank is securely seated in the correct collet or chuck before operation. A 1/8" shank is not interchangeable with 3 mm tooling.
Cutting Performance
The SD-51NF ball shape provides cutting contact around its rounded profile, making it especially useful for concave geometry, radiused cavities, internal curves, and recessed features. Unlike straight-sided burr shapes, the spherical head can engage curved surfaces from multiple approach angles, giving the operator greater flexibility when blending or shaping rounded areas.
Its compact 1/4" head provides access and control in tighter features, while the Aluma Cut tooth pattern uses wider, more open spacing than a double-cut pattern to provide 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 chart above to select the recommended operating-speed range based on the 1/4" burr head diameter and workpiece material.
Do not exceed the 70,000 RPM maximum speed for this standard-length 1/4" carbide burr. Always operate within the lower maximum speed of the burr, machine, collet, chuck, or accessory system.
Safety Tips
-
- Secure the workpiece before beginning operation.
- Confirm the 1/8" shank is properly seated and securely tightened in the correct collet or chuck.
- 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 inside curved or recessed features.
- 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 70,000 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.
Frequently Asked Questions
SHIPPING
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Standard FREE shipping is UPS Ground or USPS priority depending on size and weight. Most customers receive their order within 3-5 days from date of purchase. Faster shipping options available for additional charge. Free shipping not available on international orders. Free shipping will only be available to orders being delivered within the lower 48 states.
Refund
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