Everstampi, which has been active in the plastics industry for over 30 years, designs, manufactures and tests molds for small and medium-sized plastic articles for a wide range of industries, including cosmetics, food and beverages, cleaning products and the pharmaceutical industry.
Everstampi guides its customers through every step of the process: from presentation of mathematical models, drawings and prototypes to design, production and implementation of the molds.
For Everstampi, automation is the future, which is why they have invested heavily in technology in recent years. The company collaborates with industry-leading CAD/CAM specialists such as Autodesk and TopSolid and has made large investments in the form of machines. His workshop includes many state-of-the-art equipment, including four milling machines, four turning machines, two straightening machines, four EDMs and a drilling machine.
These choices paid off and Everstampi has become a leading manufacturer of high volume injection molds, with some of the shortest production runs on the market. In October 2021, the company was looking for a new micro-drilling solution to make precision holes in a cast component. When he needed a robust and reliable solution, he chose to invest in Sandvik Coromant tools.
Microperforation techniques are used to produce components that include medical devices and surgical instruments, aerospace components and consumer electronics. However, it is not only the small dimensions of the components that pose a processing challenge.
Manufacturers find themselves having to process smaller and smaller products in notoriously difficult materials, such as stainless steel, ceramic and titanium. Providing a high surface finish while maintaining good tool life is no easy feat, which is why many consider the prospect of frequent breakage.
In this case, Everstampi had to drill components in ISO H materials. Steels with a hardness of 53-54 HRc, which the type Everstampi uses, are difficult to machine: they generate heat when cutting and are very abrasive on the cutting edge. Although tool breakage is never intended, working with these materials makes it an eventuality that manufacturers have come to expect.
“Honestly, our goal was to get the job done with as few breaks as possible,” explains Colombo Edoardo, Production Manager at Everstampi. “We knew how difficult it would be to make so many small holes in such a hard material. We would have been satisfied even if we broke some points”.
It is not uncommon for micro drills to exhibit short tool life, especially when machining hard workpieces. If a tool that lives up to expectations is desired, the tip’s design, quality and coating must be carefully considered.
To solve their drilling problem, Everstampi chose CoroDrill® 862 with Sandvik Coromant -GM geometry. It is an ideal tool for precision drilling, capable of making holes from 0.30 to 3.00 mm in diameter. CoroDrill® The 862 is compatible with all ISO materials and is available in a wide range of tools and lengths. CoroDrill in short® 862 can make a difference in the quality of the finished product. But is it a tool made to last?
Everstampi selected five tools with different diameters ranging from 0.5 to 0.9 mm, each with the ability to drill down to depths of the hole up to nine times the diameter (xD). When Everstampi decided to dispense with the coolant supply, which would normally favor chip evacuation, Sandvik Coromant suggested the company use discontinuous penetration drilling to achieve more efficient machining.
“Discontinuous penetration drilling involves plunging the bit through the workpiece,” explains Fabio Capone, Solid Round Tools Specialist at Sandvik Coromant. “Ideally, it is sufficient to drill no more than two or three times the diameter of the tip and then bring it back to the surface”.
“This action is repeated until the hole is complete. When internal coolant is not used, as in the case of Everstampi, we recommend this drilling method as it aids the chip evacuation process, increases tool accuracy and prevents chip breakage,” adds Capone.
To Everstampi’s surprise, tool breakage was not a problem. Only one tip broke after drilling for approx. 1.5 m. “It’s not because we didn’t believe in the product, it’s simply very difficult for a micro drill to work such a hard material with excellent results and without significant breakage,” says Edoardo. “Having a single tool break during such intense drilling operations is not only amazing, it’s almost impossible.”
Despite their small size, these microtips carry a great responsibility. Making extremely precise holes in some of the hardest materials in the industry is no easy task. When Everstampi started looking for a new micro tip, it expected to fail fast and often. Using CoroDrill® However, 862 frequent tool breakage did not hinder productivity.