Coolant Selection and Filtration Aids Carbide Grinding Specialist

Carbide tools have been around a long time. Just ask John Bachmeier and his father Jacob, founder of Damen Carbide Tool, Inc. (Wood Dale, IL). Founded in 1955 on the north side of Chicago, Damen has specialized in solid carbide tooling for almost 50 years now. Jacob Bachmeier, who is still active in the company, notes that while carbide tooling is quite common today, it was quite a niche compared to high speed steel, even up to 10 years ago.

Bachmeier has witnessed tremendous changes in Damen’s business over the decades. A strong customer base that included the likes Bell & Howell, Western Electric and Westclox has given way to tier auto suppliers, aerospace component manufacturers and chip manufacturers who now require special, high precision carbide tooling. Damen’s reputation and commitment for superior quality carbide tooling has sustained the company during decades of industrial changes.

The technology of manufacturing carbide tools has also undergone dramatic changes. In Damen’s 20,000 square foot facility, you still find many manual and automatic grinding machines. “There’s still a need for these occasionally”, stated John Bachmeier, “but all the machines we have purchased in the last 10 years are, of course, CNC grinders.” To meet the growing customer requirements for special carbide tooling, Damen’s operation includes multiple grinding processes including cutter and tool grinding, ID and OD, surface, centerless, jig grinding and honing.

Water Coolant Causes Initial Problems
Typical to many grinding operations, Damen initially employed a water coolant for the majority of the grinding operations. A bank of five Schutte grinders began to have increased maintenance issues including carbide residue build up on ball screws and corrosion of moving mechanical parts due primarily to the inherent nature of water coolant. “We recognized that our water supply was probably more ‘rusty’ than desired,” stated Bachmeier, “so we launched into a program of trying to condition it.” When several attempts netted only marginal results and the water coolant continuing to look like ink, Bachmeier began to research alternatives. He knew that utilizing oil as a coolant would produce the desired results in terms of product finish and quality, but the costs in cycle times, raw materials and disposal were also compounded by the additional capital purchases for filtration, chillers, etc. The addition of a series of band filters and centrifuges filtering anywhere between 5 and 20 microns did not produce the quality that Bachmeier was seeking.

At this point, Bachmeier had an opportunity to have a conversation with an industry colleague who had recently installed a centralized filtration system from Transor Filter (Elk Grove Village, IL). Further investigation led to conversations between Damen and Transor that resulted in the installation of a three vessel centralized Transor System to service the six Schutte grinders.

The Switch To Oil, Centralized Filtration and Reduced Maintenance
Bachmeier discovered immediate benefits after installing the Transor. With the patented Transor system, the coolant is filtered to one micron absolute. Using compressed air to automatically clean the filter elements also eliminated an on-going replacement of expensive filter media required with the previous systems. “There was a noticeable difference in the cleanliness of the oil”, said Bachmeier, “By having such clear oil, once we cleaned our machines, they stayed that way.” He went on to note that with the one micron filtered oil, the excessive carbide residue was gone as well as the carbide build-up on grinding wheels.

They also discovered that with the automatic back flushing system, the carbide was deposited into a sludge bag for easy removal and reclamation. Bachmeier noted that previously with the centrifuges, operators were spending at least an hour per day in clean-up, the Transor’s cleaning cycle requires no operator involvement or machine downtime. Damen began to experience virtually maintenance-free operation. In the four years of operating the Transor system, the filter elements have not required changing as well as the oil has yet to be changed, only topped off.

One Micron Oil Helps To Expand Business
One of the challenges facing Damen’s sustained growth was the very thing that makes them unique. “Our capability to produce high precision specials,” said Bachmeier, “has required us to be creative problem solvers regarding adding CNC technology. I think it would be fair to say that we’re not a typical user of any CNC grinding equipment.”

He went on to say that both the Schutte and Walter technicians were extremely knowledgeable about fluted endmill production, but that isn’t the business they are in. But Damen has applied their considerable engineering skills to adapt “fluting” on cutter & tool grinders to teeth on micro carbide saws where in some instances they are holding 0.0002”. Bachmeier also referenced a recent job on their new Studer where workpieces were 300 lbs. each of solid carbide. “We had stock removal of 3/8” which is not your typical fine grinding application,” he laughed. “We also produced a tool holding 0.0000005” (1/2 millionth) and 0.020” (20 thousandths) in the hole on that machine

Damen being all about closer tolerances and better finishes recognized that filtration was the key. Using what they learned from the Transor initially installed on the Schutte grinders, a second system was installed on a cell with a Walter grinder and a double disc machine for fine grinding. A third system is being installed on the Studer.

Bachmeier was quick to acknowledge consistent, clean and cool oil was essential for maintaining the quality of the tools being produced. “With the sophistication of a machine, like the Studer,” he said, “the maintenance issue is huge.” He went on to also point out that Transor’s clean oil keeps all the moving parts from corroding, carbide build-up on the abrasive wheels id virtually eliminated and the environmental issues surrounding reclamation of carbide and disposal of coolant are completely under control.

Well into there second generation of manufacturing carbide tooling, the grinding process that was unique even 10 years ago has become quite a competitive industry. “With multiple grades of carbide and ceramics being utilized in today’s tools,” Bachmeier noted, “ Damen’s ability to keep pace with the market will require us to continue uncovering technology like we found with Transor.”