AT-2 thread mill delivers exceptional tool life, consistent machining performance, and consolidated tooling in 17-4PH stainless steel food equipment production.

Gulfco Manufacturing, based in Pueblo, Colorado, USA, is a family-owned company with a legacy spanning more than 70 years. Its origins trace back to 1946 in Emeryville, California, where it operated under the name Atlas Pacific Engineering Co. In 1986, the company relocated to Pueblo, Colorado, focusing on the production of food processing equipment. Over the next three decades, Atlas Pacific experienced steady growth and success, culminating in the acquisition of Magnuson CCM, Luthi Machinery, and Brown International. In 2018, the Engineering, Sales, and Service divisions moved to Centennial, Colorado, while the Pueblo facility remained active. This transition led to the creation of Gulfco Manufacturing, which assumed responsibility for all acquired product lines and expanded its offerings to include third-party manufacturing services.

Today, Gulfco Manufacturing stands as a vital contributor to the global food supply chain, specializing in the production of components, equipment, and industrial solutions for the food processing and packaging sectors. The company offers a comprehensive suite of manufacturing services, including precision machining, fabrication, welding, and assembly. Headquartered in Pueblo, Colorado, Gulfco Manufacturing employs 120 staff and operates out of a state-of-the-art facility spanning over 160,000 square feet.

Gulfco Manufacturing recently faced challenges with tap breakage and inconsistent tool life during the production of stainless steel 17-4PH (38 HRC) inserts used in food processing equipment. This component has been in production for over four years, with an estimated annual volume of 2,000 pieces. Each workpiece requires two blind holes, 0.1336 inch in diameter and 0.406 inch deep, to be drilled and threaded to an 8-32 2B UNC specification. Machining is performed on a Mazak HCN-6000 4-axis horizontal machining center equipped with a CAT50 taper.

Gulfco Manufacturing initially utilized 8-32 spiral flute bottom taps and 8-32 thread mills from three different brands but was dissatisfied with their performance. To address the issue, Michael Dougan, Metalworking Specialist at MSC Industrial Supply Co., introduced Steve Lauman, Northwest Territory Sales Manager at OSG USA, to Gulfco Manufacturing’s facility. After a thorough evaluation of the application, Lauman recommended OSG’s A Brand 8-32 4-flute AT-2 thread mill (EDP# 1664500011) as a solution to improve tool performance and reliability.

OSG’s AT-2 is a high-performance carbide thread mill designed with an end-cutting edge, enabling it to combine pilot hole drilling and threading into a single operation—even in challenging materials like high-hardness steel. Engineered for durability and precision, the AT-2 features a uniquely reinforced cutting edge geometry that minimizes tool bending. Its left-hand cut configuration supports climb milling, which helps extend tool life by reducing deflection and heat generation. Additionally, roughing teeth are incorporated to evenly distribute cutting loads.

To further enhance performance, the AT-2 is coated with OSG’s proprietary DUROREY coating, which effectively suppresses chipping in high-hardness applications. This design eliminates sudden tool breakage caused by poor chip evacuation, allowing operators to machine with confidence. By streamlining drilling and threading into a single step, the AT-2 boosts processing efficiency and lowers tooling costs. It is suitable for a wide range of materials, including high-hardness steel, stainless steel, non-ferrous metals, and heat-resistant alloys.

The competitor’s TiCN coated 4-flute thread mill was operated at a spindle speed of 10,000 RPM, a cutting speed of 320 SFM, and a feed rate of 9.5 IPM, achieving an average tool life of 24 workpieces. In contrast, OSG’s AT-2 thread mill was run at a spindle speed of 4,621 RPM, a cutting speed of 148 SFM, and a feed rate of 1.75 IPM—delivering an impressive average tool life of 500 workpieces.

At first glance, the competitor’s thread mill may appear to offer faster cutting parameters. However, it requires a separate drilling operation prior to threading, necessitating an additional tool and setup. In contrast, OSG’s AT-2 thread mill integrates pilot hole drilling and threading into a single operation, streamlining the process. When accounting for total tooling requirements, tool life, machine downtime, tool changeover, machine utilization, and overall tooling costs, the AT-2 delivered a cost savings of $2,687 USD for this specific part and size. Following the success of this cutting trial, the AT-2 has been adopted for five additional sizes, with projected savings of $13,000 to $15,000 USD—excluding further reductions in downtime and rework.

Any machinist knows that breaking a tool during one of the final machining operations can be extremely costly, with serious implications for production efficiency and delivery timelines. Gulfco Manufacturing is committed to innovation and continuous improvement, while honoring the legacy and contributions that have shaped its success. By adopting OSG’s AT-2 thread mill, Gulfco Manufacturing has achieved stable threading performance and significantly reduced costs in its stainless steel insert production.

“The AT-2 is the total solution,” said Wayne Schwarze, Manufacturing Engineer at Gulfco Manufacturing. “It eliminated scrap entirely and delivered substantial process improvements and cost savings.”

This article was previously featured on OSG's blog.