Drill Helps Shop Balance Cycle Time, Part Quality

Faced with a troublesome drilling operation, Mill Equip Products was running out of alternatives to reduce cycle time. It seemed the only way to improve productivity was to purchase a new option for the shop’s milling machine—an option estimated to cost upwards of $5,000. With a new drill from Precision Dormer, however, the shop was able to significantly increase productivity and finish the job more than 2 weeks faster than with its previous tool.

Mill Equip was founded in 1986 as a brokerage firm representing local machine shops. In 1991, the need for better control of production and quality led founder Sam Cantavespre and his sister, Frances Bertella, to open their own shop. Today, the company employs nine people, and its 10,000-square-foot facility houses a mixture of manual and CNC mills and lathes as well as a weld shop and other secondary and finishing equipment.

Located in Bessemer, Alabama, the family-owned shop serves customers ranging from manufacturers that need equipment repairs to OEMs that source parts out for resale. It has a strong presence in steel mills, to which it supplies both new parts and rebuilt used parts. The company machines components out of a variety of materials, including steel, bronze, brass and plastic in quantities ranging from a single part or production run to several thousand.

Recently, Mill Equip took an order for a job that required drilling thousands of holes in steel parts used as precision chain links. The shop used a conventional drill to cut the holes through three ¹/₄-inch-thick pieces of low-carbon steel. Each hole took approximately 1 minute to produce—a cycle time that was entirely too long for Mr. Cantavespre. Completing jobs quickly and efficiently is very important for Mill Equip, as many customers call in the middle of the night to fix a part. "Steel mills can lose as much as $100,000 per minute when they are not producing their product," he explains.

Just when he thought he had exhausted all alternatives except for the expensive milling machine option recommended by his colleagues and peers in the industry, Mr. Cantavespre spoke with Precision Dormer sales representative Joe Zeigler. Mr. Zeigler brought in a Dormer R458 MP-X carbide drill for a test run and explained the correct feeds and speeds needed to maximize its performance.

"I really thought he was crazy," Mr. Catavespre admits. "I thought, ‘there is no way that drill will ever hold up under those conditions.’" Nevertheless, when Mr. Catavespre hit the cycle-start button on his Fadal 4020 VMC, five holes were drilled to size in the test piece in less than 30 seconds. "It was definitely one of those moments where you are expecting the worst, yet walk away feeling very impressed with the product," he says.

The R458 MP-X drill is made of sub-micrograin carbide coated with a multi-layer titanium aluminum nitride. According to the manufacturer, this combination provides toughness, long-lasting cutting edges and wear protection, resulting in higher productivity and longer tool life. The drill’s flute geometry is designed for efficient chip evacuation, while the 140-degree point angle is suitable for a wide range of materials.

Mill Equip was able to run the drill at a high enough rpm and penetration rate to avoid peck cycle or interruption—it cut the holes with a straight plunge. In addition, the tool does not require the center drilling required with most conventional drills, eliminating an entire step in the process. And the shop could complete the operation without having to stop in mid-cut to evacuate chips.

The quality and performance of the drill were just what the shop needed. The tool immediately increased production while decreasing work time, enabling the company to finish the job in less than one week, compared with three weeks using the previous drill. Based on this performance, the shop has since purchased several other MP-X drills. Speed rarely equals quality, but Mr. Catavespre says his shop has now found a perfect balance.

"It has really saved me a lot of time," he says. "Without sacrificing quality, I’ve been able to lessen the load on drill time. I’ve been able to pick up more production hours, which means more business, and in turn, more money."