Sunnen M27 NM75 CBN Cubic Boron Nitride Hone Stones Set 4 pcs 320 Grit

Description

Product Overview

The Sunnen M27 NM75 CBN honing stone set is engineered for high‑precision metalworking environments where surface integrity and dimensional accuracy are paramount. Each stone in the set is fabricated from premium cubic boron nitride (CBN), a material renowned for its extreme hardness, thermal stability, and resistance to wear. The 320 grit rating provides a fine balance between material removal and surface finish, making these stones ideal for a wide range of applications, from rough shaping to final polishing. The set includes four compact bars, each measuring approximately 4 × 2 × 2 inches, allowing easy integration into standard honing machines and hand‑held tools. The product dimensions and lightweight design reduce machine load while delivering consistent performance across multiple workpieces.

Usage

These CBN honing stones excel in CNC machining centers, tool and die grinding stations, and manual honing setups. Their durability makes them suitable for machining hardened steels, stainless alloys, and exotic materials such as titanium and nickel‑based superalloys. Operators can employ the stones for sharpening cutting tools, restoring the geometry of end mills, and achieving tight tolerances on aerospace components. The compact bar format enables quick changes between different tool holders, minimizing downtime and maximizing productivity. Because CBN maintains its cutting ability at elevated temperatures, users experience reduced heat‑related deformation, leading to longer tool life and more consistent surface finishes.

Why Choose Us

Sunnen has a legacy of over a century in abrasive technology, and the M27 NM75 series reflects that heritage through rigorous quality control and material science expertise. Each stone undergoes a multi‑stage bonding process that ensures uniform grain distribution and eliminates internal stresses that could cause premature failure. The CBN coating is applied using a proprietary sintering technique that guarantees adhesion even under the most demanding machining conditions. Sunnen provides a comprehensive warranty and responsive technical support, offering guidance on optimal operating parameters, stone life expectancy, and troubleshooting. Customers benefit from a proven track record of reliability, backed by a global network of distributors and service centers ready to assist with any post‑purchase needs.

Key Features

• Premium CBN composition delivers superior hardness and wear resistance for extended stone life.
• 320 grit rating provides a fine finish while maintaining efficient material removal rates.
• Compact 4‑piece bar design fits standard honing machines, reducing changeover time.
• Consistent performance on hardened steels, stainless steels, titanium, and nickel alloys.
• Sunnen technical support and warranty ensure confidence and after‑sales assistance.

FAQ

What materials can I hone with these CBN stones?

The Sunnen M27 NM75 CBN stones are suitable for hardened steels, stainless steels, titanium alloys, nickel‑based superalloys, and other difficult‑to‑machine materials where conventional abrasives would wear quickly.

How often should the stones be replaced?

Stone life depends on machining parameters, material hardness, and operating conditions. In typical CNC machining of hardened steel, a set can process several hundred workpieces before performance degrades. Sunnen recommends inspecting the stone surface regularly and replacing when the grit becomes glazed or the cutting efficiency drops noticeably.

Can these stones be used in a hand‑held honing tool?

Yes. The 4 × 2 × 2 inch dimensions are compatible with many hand‑held honing devices. Ensure the tool holder provides secure clamping to avoid movement during operation.

Do the stones require any special cooling or lubrication?

Standard coolant or light oil is sufficient. CBN’s thermal stability allows it to operate effectively with typical machining fluids, helping to dissipate heat and improve surface finish.

Is there a recommended speed range for optimal performance?

For most CNC applications, a spindle speed between 2,000 and 5,000 RPM yields the best balance of material removal and surface quality. Adjust speed based on the specific material and desired finish, consulting Sunnen’s technical data sheets for detailed guidelines.