GOmill PRO and HARVI™ II TE: The Perfect Solution for High-Performance Solid End Milling

The GOmill PRO isn’t just another end mill, it’s a go-to for smooth, precise milling. Whether tackling side and shoulder milling, pocketing, slotting or helical milling, this tool is built for versatility. The 4-flute design, asymmetric divided flute and variable helix angle keep things running stable and chatter-free, while the multilayer coating adds durability to keep you cutting longer. The tapered core facilitates better chip evacuation and tool strength. Another highlight is the special relief design, which increases edge strength, offering better vibration control and flexibility when working with different materials.

"The GOmill PRO gives you all the normal features of an end mill and a very good coating, making it perfect for a broad range of materials," said Tamir Sherif, senior global product manager of marketing. “The goal of GOmill PRO is to cover 80% of applications for job shop companies, offering a good price-performance position.

The HARVI II TE solid end mill is the newest member of Kennametal’s HARVI family, built for machinists who need both high performance and versatility when working with a variety of materials. What makes it truly stand out is that it’s the only 5-flute end mill designed to tackle aggressive cutting tasks like high angle ramping and plunging, giving it an edge in tough machining conditions. The open 5-flute design and reinforced core work together to increase material removal rates (MRR), extend tool life and improve chip evacuation.

“If you are in the high-performance arena and need your application to be more specific, then you have to go with HARVI II TE,” said Katie Myers, global product manager of marketing. “The HARVI II TE features a unique end face, five-flutes, W-shaped flutes, chip gashes, and a proprietary coating, which gives you absolutely perfect application results.” 

One of the key innovations of the HARVI II TE is its front-end design, which significantly improves the tool’s Z-axis capabilities, allowing for more precise and efficient cutting operations. The proprietary W-flute shape enhances chip evacuation and strengthens the core. Additionally, the eccentric relief design increases edge strength, resulting in longer tool life and a wide material application range.

Understanding the specific applications of end mills like the GOmill PRO and HARVI™ II TE is crucial for maximizing their potential and ensuring optimal performance. These tools are designed for a variety of tasks. For instance, the GOmill PRO excels in slotting, profiling, and contouring and is perfect for machining engine components and structural parts.

The HARVI™ II TE, on the other hand, is versatile with its heavy-duty milling and dynamic milling capabilities. It can do both operations really well. It is particularly effective in the aerospace and defense industries, where precision and reliability are paramount. This tool excels in roughing and finishing operations, making it suitable for machining complex geometries and hard-to-machine materials like titanium and stainless steel.

Knowing the specific applications is essential for optimizing your manufacturing processes, ensuring high-quality output.

To get the best performance from the GOmill PRO and HARVI II TE end mills, it’s important to understand their cutting parameters. Depending on the diameter and material hardness for both end mills, feed per tooth (Fz) varies in each application. Additionally, larger tool diameters generally allow for higher feed rates while harder materials require lower feed rates and speeds to prevent tool wear.

“Material removal rate is also affected by the flute count and cutting parameters. With the 4 flutes in GOmill PRO, you’re able to increase your material removal rate by increasing your radial stepover due to having more flute space to evacuate chips,” said Myers. “With the 5 flutes of HARVI II TE, you can increase your MRR automatically with the extra flute, which also gives you the potential to increase your MRR with dynamic milling applications or high angle ramping and plunging that the TE family excels at.”

By adjusting these parameters, you can achieve optimal performance, extend tool life, and ensure high-quality machining results.

When it comes to the GOmill PRO and HARVI II TE, the diameter of these end mills isn’t just a number—it means the difference between achieving optimal performance and facing machining challenges.

GOmill PRO is available in common diameter ranges, with a variety of options in the 6 – 12 mm range, making it ideal for general-purpose machining tasks.  On the other hand, it is also available as small as 2 mm, making it a versatile option for more detailed work and tight spaces, providing precision at slower feeds.

The HARVI II TE, with its unique 5-flute design, is built for aggressive cutting tasks like ramping and plunging, making it a standout in tough machining conditions. For heavy-duty applications, a larger diameter can bring more strength to the table, offering greater stability, which reduces the risk of tool deflection and chatter. 

Now, let’s talk about the unsung heroes of the GOmill PRO and HARVI II TE—the grade and coating. They play a crucial role in enhancing performance and durability. Both coatings are gold/copper and designed to offer several benefits, including increased wear resistance, reduced friction, and improved heat resistance. Additionally, these coatings assist operators in visually inspecting the edges more effectively.

GOmill PRO end mills feature a multilayer TiN/TiAlN coating which provides high performance at medium to high cutting speeds, particularly when working with steels, stainless steels and cast iron. The multilayer structure of the coating enhances the tool’s durability, allowing it to maintain sharpness and cutting efficiency over extended periods.

The HARVI II TE end mills are equipped with KCPM15A and KSCM15A multilayer coated grades. They are thinner than Kennametal’s previous coatings and designed for a sharper and more defined cutting edge. The grades are also smoother which helps with chip evacuation and therefore tool life. The coatings are designed to withstand high temperatures and abrasive wear, making it ideal for machining a wide range of materials, including high-strength steels, stainless steels and high-temperature alloys.

 “KCSM15A and KCPM15A are proprietary coatings that demonstrate significant improvements in tool life due to their superior edge definition,” said Myers. “The coating is the final touch on HARVI II TE that truly elevates it to a high-performance class of its own.” 

Selecting the right solid end mill is essential for achieving high productivity, precision and cost savings. The GOmill PRO offers versatility for general-purpose machining, while the HARVI II TE is built for a variety of aggressive, high-performance applications and materials. By understanding application needs, cutting parameters, and tool selection, machinists can optimize machining performance, extend tool life, and improve overall efficiency.