by Bernard Martin

Unlock the full potential of your composite machining with Decatur Diamond's high-performance cutting tools! From carbon fiber and glass fiber reinforced polymers to metal matrix composites, their extensive range includes versatile routers, honeycomb routers, compression routers, diamond cut routers, and drilling products.

Engineered for precision, durability, and efficiency, their tools minimize delamination and fiber pullout while ensuring clean, precise cuts and extended tool life. Discover why Decatur Diamond is the industry leader in advanced tooling solutions for composite materials.

Diamond Coated End Mills
Decatur Diamond 's Diamond Coated End Mills are designed for high-performance machining of non-ferrous materials. With potentially the best diamond adhesion in the coated tool industry, these tools offer coating thickness and crystal size options to meet various application requirements. Available in square, corner rounding, ball, and profiling geometries, these end mills ensure superior performance and tool life. Sizes start from 0.015” (1mm) and can be customized for special applications.

• ​All standard grade D25 endmills are produced to +0.000/-0.001 on diameter, -0.0001/-0.0003 on the shank, 0.001 runout,+0.060/-0.000 on flute length and +/-0.060 on OAL.
• All standard grade D27 endmills are produced to +0.001/-0.001 on diameter, -0.0000/-0.0003 on the shank, 0.002 runout, +0.060/-0.000 on flute length and +/-0.060 on OAL.
• All Ultra Premium grade D25 endmills are produced to +0.000/-0.0005 on diameter, -0.0001/-0.0003 on the shank, 0.001 runout, +0.060/-0.000 on flute length and +/-0.060 on OAL.
  

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Decatur Diamond’s commitment to innovation and quality makes our tools the preferred choice for machining composite materials. With tailored solutions and a focus on reducing operational costs, our high-performance tools help you achieve superior results in your machining processes.

Durability and Longevity
One of the foremost advantages of carbide-tipped tools is their exceptional durability and longevity. These tools combine the best of both worlds, featuring a tough steel body with a carbide insert at the cutting edge. When compared to solid carbide tools, carbide-tipped tools often outlast them due to their ability to withstand high-impact applications. In contrast, HSS tools are more prone to wear and require frequent regrinding or replacement

Versatility​
​Carbide-tipped tools offer a remarkable level of versatility. The carbide inserts are available in various grades, each tailored to specific machining tasks. This adaptability allows users to choose the ideal carbide grade for their application, optimizing tool life and performance. In contrast, solid carbide tools, while highly capable in specific applications, lack the flexibility to adapt to various materials and machining conditions. HSS tools, though versatile, may not match the cutting speed and precision of carbide-tipped tools in demanding applications.

Cutting Speed and Efficiency
Carbide-tipped tools excel in cutting speed and efficiency, making them a preferred choice for high-production environments. The hardness of carbide allows for faster cutting speeds, which translates to reduced machining time and increased productivity. Solid carbide tools come close but may not always match the speed and efficiency of carbide-tipped tools, especially when it comes to demanding materials like stainless steel or hardened alloys. HSS tools, on the other hand, are often outpaced in terms of cutting speed and efficiency.

Heat Resistance
Heat resistance is a critical factor in machining, especially when working with materials that generate high temperatures during cutting. Carbide-tipped tools have superior heat resistance compared to HSS tools. The carbide can endure high temperatures without losing its cutting edge, ensuring consistent performance even under demanding conditions. Solid carbide tools have good heat resistance but may be prone to chipping or breakage when subjected to extreme heat, which is less of an issue for carbide-tipped tools.

Cost-Effectiveness
While the initial cost of carbide-tipped tools may be higher than HSS tools, their durability and longevity make them a cost-effective choice in the long run. Solid carbide tools, while durable, can be more expensive and may not justify their cost in all applications. HSS tools, although cheaper initially, may need more frequent replacements and regrinding, ultimately incurring higher costs over time.

In the world of cutting tools, carbide-tipped tools stand out as a versatile, high-performance, and cost-effective solution. Their unique combination of a tough steel body with a carbide insert at the cutting edge offers durability, versatility, high cutting speeds, heat resistance, and cost savings. While solid carbide and high-speed steel tools have their merits in specific applications, carbide-tipped tools are the go-to choice for industries and machinists looking to maximize efficiency and quality across a wide range of machining tasks. Whether you're working with metals, plastics, or composites, carbide-tipped tools provide a winning edge in the world of precision cutting and machining.

written and edited by ​Bernard Martin

Data Flute, the renowned end mill manufacturer who pioneered the adoption of the 3 and 5 flute end mills for stainless steel and exotic alloys nearly 30 years ago, has recently introduced two new groundbreaking end mills— the SSI-5plus and SSI-7. These cutting-edge tools are designed to set the standard for versatility and performance in (P)steel, (H)hardened steels, (M)stainless steels, (S)super alloys and even (K)cast iron. 

Data Flute unveils the SS-7 end mill, a cutting-edge solution designed for high-efficiency machining in ferrous alloys. This finisher showcases a new carbide substrate, ensuring superior durability and outstanding tool life, even in demanding applications.

Engineered with specific geometry tailored for titanium alloys and stainless steels, the SS-7 features seven flutes with an unequal index and a constant helix, promoting efficient chip evacuation and reduced cutting forces.

This non-center cutting tool, available in both RH-C and RH-H configurations, boasts a continuous cutting edge for seamless machining.

The SS-7 end mill sets a standard with its tight tolerances, including a shank diameter held to h5 specifications and a cutting diameter precision within -0.001"/-0.002". The corner radius further enhances precision, offering +0.001"/-0.001". Machinists can expect not only high efficiency but also superior surface finishes, making the SS-7 a standout choice for those seeking precision, longevity, and exceptional performance in ferrous alloy applications.

• Material Composition - SS-5plus ​ and SS-7 end mills are crafted from high-quality micro-grain carbide, ensuring exceptional durability and resistance to wear.
• Geometry and Flute Design - The  SS-5plus features a unique 5-flute design, providing increased stability and reduced vibrations during cutting operations. The SS-7, with its 7-flute configuration, is engineered for high-speed machining, delivering efficient chip evacuation and improved surface finish.
• Coating Technology - Both end mills come equipped with advanced coating technologies such as TiALN (Titanium Aluminum Nitride) or TiCN (Titanium CarboNitride), enhancing tool life and facilitating high-speed machining applications.
• Cutting Parameters - The SS-5plus and SS-7 are optimized for a wide range of materials, including steels, stainless steels, and exotic alloys, showcasing versatility in machining operations.

These end mills exhibit exceptional performance in applications such as slotting, roughing, and finishing, making them suitable for various industries, including aerospace, automotive, and mold and die.

Carbide cutting tools have revolutionized various industries with their exceptional hardness, heat resistance, and longevity. Understanding the intricate details of the cutting process and the meticulous production of carbide tools sheds light on their unmatched performance in the world of machining. Whether it's the intense forces at the cutting edge or the precise control of cobalt binder content and carbide grain size, carbide tools continue to shape the future of manufacturing and engineering.

by, Bernard Martin

As carbide end mills gain higher and higher speeds and metal removal rates there has also been a trend by round tool manufacturers to tighten up the tolerances on both the cutting diameter and the shank diameter to improve concentricity. At the same time, shrink fit holders have become more and more popular because they hold a tighter concentricity as well.  To achieve this both the shank and the bore now have similar surface finishes and this has led to a problem  The tools pull out in the cut.

Shrink fit holders are the most accurate for TIR as the toolholder engages completely around round shank tools with a bore tolerance of -0.0001" to  -0.0003".  As high performance end mills have tightened shank tolerances to the same range of -0.0001" to  -0.0003" they have used finer and finer grain grinding wheels which give the shanks a 'shiny' appearance. 

Shiny means that the superfinished shank has a lower coefficient of friction. So, although the TIR is tighter, the shank is more "slippery".   End mills traditionally had surface finish of about 8 μin on the tool shank. But that's changed.  It's been recommended that tool shanks used in shrink fit holders should not have a finish finer than 16 μin. for optimum holding power, but tell that to the guy who just superfinished the end mill to a super cocncentric tolerance that you don't want it looking that good.

Everyone know that the last thing you want is for the end mill to slip in the middle of a heavy cut or on the finishing pass of a high tolerance part.  These 'hi performance' end mills, often times have higher helix angles which are great for ejecting chips but also create a higher pull out force on that slippery shank. And reducing the helix angle is not the answer.

We  already know that the gripping pressure is a function of the interference between the tool shank  and the shrink fit toolholder bore. Most shrink fit holders have a already bore surface finish of between 12 μin. and 16 μin.  So they are ground to a very high tolerance and have about the same surface finish as the toolholder shank.

End mill manufacturers and machinist have tried a variety of methods over the years to stop the tools from pulling out. This has ranged from grit blasting the shank to rubbing chalk on the shank, but most everyone in the industry has felt that the problem really needs to be addressed by the longer life toolholder rather than the replaceable cutting tool.

Weldon Tool has announced a running change to the appearance of all Weldon Premium carbide endmills regarding raised land transition area from the back of the clearance face to the flute.

This design change also provides an appearance more consistent with most all tungsten carbide endmills.

Weldon further states: "This is only a functional appearance change. Both internal and customer field tests have confirmed that users will still experience the same outstanding performance of Weldon Premium carbide endmills as they have in the past."