compiled & edited by Bernard Martin

The Weldon flat quickly gained popularity and became a standard feature in many milling tools. Machinists embraced it for its reliability and the tangible improvement it brought to the overall machining process. Its success was emblematic of how a seemingly simple yet ingenious design modification could elevate the efficiency and accuracy of machining operations.

However, with the continuous evolution of the machining industry, especially with the rise of CNC machining and the increasing demand for higher precision, the prevalence of the Weldon flat began to diminish. Two primary factors contribute to the decline in the use of Weldon flats: Tool Balance and Runout (TIR).

​Tool balancing, or the lack thereof, poses a significant challenge. Many high-end machine tool manufacturers stipulate the use of only "balanced tooling," underscoring the critical need for proper balancing of Weldon Flat Toolholders before utilization. The removal of material from the tool shank introduces inherent imbalance, leading to potential harmonic distortions in part finish, particularly in high-speed machining environments.

Additionally, TIR presents a challenge in today's high-tolerance machining landscape. The design of Weldon-style endmill holders inherently displaces the cutter off-center, inducing runout (TIR) that can significantly reduce tool life and compromise the surface finish of the machined part.

That said, it's important to note that Weldon flat holders can still prove advantageous, especially in scenarios involving rough machining and the removal of substantial material. This is particularly relevant in the Aerospace sector, where machining critical components like expensive wing spars carries the risk of tool pullout—an occurrence that can be financially and structurally detrimental. When dealing with challenging materials like Titanium, characterized by high torque forces during machining, Weldon Flat holders remain well-suited for applications that demand an aggressive depth of cut at relatively slow spindle speeds.

While the Weldon flat remains a valuable feature in many machining applications, its decreasing prevalence in certain advanced CNC machining requirements reflects the dynamic nature of the industry. New technologies and methodologies have emerged, emphasizing the need for even greater precision and stability within cutting tools to meet the demands of contemporary machining practices.

​The innovation of the Weldon flat marked a significant chapter in the history of machining, revolutionizing tool retention and setting new standards for reliability and precision. Its popularity soared in its heyday, but the ever-evolving requirements of modern CNC machining have reshaped the landscape, emphasizing the continuous quest for higher levels of accuracy and performance in the field of metal cutting.

Heritage Cutter is the parent company to the iconic metalcutting industry names Brubaker, Data Flute, Decatur Diamond and Weldon Tool each with their own specialization in cutting tools

Heritage Cutter is the parent company to the iconic metalcutting industry names Brubaker, Data Flute, Decatur Diamond and Weldon Tool. Each of these companies names reflect their longstanding reliability, quality and commitment to industry has made them a trusted source to distributors and manufacturers for generations.  

Each of these companies has had a niche place in the market as well as some product overlap over over the last few decades.  In order to clarify where each brand fits under the Heritage Cutter umbrella, and to set a strategic outlook, Heritage Cutter has outlined the speciality areas that each of the brands it taking moving into the future. 

Data Flute, a distinguished brand under the Heritage Cutter umbrella, has been a stalwart leader since its inception in 1976. Known for its unwavering commitment to excellence, Data Flute has carved a niche as a premier designer and manufacturer of both standard and special high-performance solid carbide cutting tools.

The mantra, "The most demanding machinists demand Data Flute!" encapsulates the brand's dedication to meeting and exceeding the expectations of machinists who demand nothing but the best. Over nearly five decades, Data Flutee has established itself as a trusted name synonymous with high-performance, application-specific carbide cutting tools.

For over 140 years, Brubaker Tool, a distinguished member of the Heritage Cutter family, has been a cornerstone in the industry, proudly serving with high-performance, special, and standard taps & threading tools. Established in 1881 in Millersburg, PA, Brubaker Tool began its journey by supplying taps to the burgeoning railroad industry, laying the foundation for a legacy that has endured for over a century.

The commitment to excellence is etched in the very fabric of Brubaker Tool. With a wealth of experience, the brand has evolved to become a leading source of American-made industrial cutting tools. Over the years, Brubaker has built upon its enduring stability, reliability, and unwavering commitment to quality, earning its status as a trusted source for distributors and manufacturers for generations.

In the specialized tapestry of Heritage Cutter's family of companies, Weldon Tool stands as a beacon of craftsmanship, quality, and a commitment to customer service that has endured since its founding in 1918. Rooted in a legacy that spans over a century, Weldon Tool has evolved into a trusted source for quality high-speed steel (HSS), cobalt, and carbide round tools, with a distinct emphasis on engineered specials.

From its humble beginnings as a two-man shop in downtown Cleveland, Ohio, Weldon Tool has grown into a powerhouse, designing, manufacturing, and delivering a diverse range of cutting tools. The original dedication to craftsmanship and quality that marked its inception remains a constant thread woven into the fabric of the company.

Nestled within the Heritage Cutter family of companies, Decatur Diamond is the home of innovation and expertise in diamond-based cutting tools. The brand's lineage is intricately tied to some of the earliest adoptions of diamond-based technologies in the cutting tool industry, showcasing a history marked by success and innovation.

​Under the banner of "When every cut counts, count on Decatur Diamond," this brand is dedicated to delivering diamond and PcBN-based cutting tools. With a comprehensive range covering indexable milling cutters, fixed pocket brazed tools, complex monobloc solutions, and CVD diamond-coated tools.

At the forefront of Decatur Diamond's contributions is the Ultra-Mill, an early and remarkably successful indexable platform for diamond tools. This innovation underscored the brand's commitment to pushing the boundaries of what was possible in the realm of cutting materials. Similarly, the DIAbide line emerged as one of the original CVD diamond carbide round tool brands, solidifying Decatur Diamond's reputation as a trailblazer in the industry.

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."