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END USER: Crowley Tool Co., (615) 824-5594, www.crowleytool.com. SOLUTION PROVIDER: Schütte LLC, (800) 668-4035, www.schutteusa.com. CHALLENGE: Enhance reliability when grinding round tools. SOLUTION: A new 5-axis CNC tool and cutter grinder with linear-drive technology.

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Crowley Tool Co. specializes in designing and manufacturing custom insertable form tools for all makes and models of multiple- and single-spindle screw machines. Crowley Tool, Hendersonville, Tenn., can work from customer part prints and process layouts to produce tools to overcome challenging applications.

The toolmaker does a significant amount of conventional, or manual, grinding to produce inserts. "Because so much of our work is unique, with maybe 20 pieces being a big order for us, we spend considerable time in setup and fixturing time," said Ed Crowley, company president.

Eddie Boland, Crowley Tool machine operator and toolmaker, says the Schütte 325linear grinder allows him to quickly produce flutes in tools, owing to the subroutines and macros on the machine. All images courtesy Justin Maxey, Crowley Tool.

About 10 years ago, Crowley Tool decided it wanted to make more round cutting tools and saw a 5-axis CNC WU305linear grinding machine from Schütte LLC, Jackson, Mich., at a trade show. The machine was more suitable than the company's existing equipment for producing round tools, Crowley said, and "It had some amazing features that we knew would make a difference for our operation."

However, the toolmaker's budget at the time prevented the purchase of a new grinder, so it opted for a used one instead, he added.

The used grinder enabled Crowley Tool to significantly shorten the time it took to produce a round tool, from about 2½ hours to 30 minutes, but the previous owners hadn't treated the machine with a lot of TLC, speculated Eddie Boland, a machine operator and toolmaker at Crowley Tool. "I feel like it had been abused," he said.

As a result, Boland said Crowley Tool experienced reliability issues with the grinder. The toolmaker was able to upgrade the grinding software, but that required replacing the machine's computer.

Eddie Boland said he appreciates the remote diagnostic ability of the CNC, which allows Schütte support to "look inside" the machine for troubleshooting and cutting path suggestions.

When programming and software questions arose, Schütte software and programming specialist Scott Topa was quick to respond, according to Boland. Topa said, "We have a team of engineers developing specialized grinding software, in conjunction with our CNC supplier, to allow customers the ability to create their own programs and adapt to changing conditions of materials without a problem."

Boland noted about 60 percent of the tools Crowley Tool makes are carbide and the rest are M-42 and T-15 HSS, with tolerances as tight as 0.0002" (5.1µm).

Eventually, Crowley decided to replace the grinder it bought used and purchase a new Schütte 325linear grinder with the latest generation of SIGSpro grinding software, which together provide modular flexibility. He said the new machine enabled the company to make a significant leap forward in its production capabilities.

"We run some very complex fluting patterns, with ID and OD relief and stepped configurations," Crowley explained. "Often, our customers require three-, six- and 12-set packages. As a lot of our customers are doing automotive, defense, aircraft, valve stem, connector, transmission and specialized fitting work, they have exceedingly high quality expectations. So do we."

On the new machine, the grinding software offers a simple, Windows-based menu and onscreen 3D simulation of the cutting path, according to Schütte. Simulations can also be run offline on a PC, increasing machine uptime and eliminating the need for additional simulation software.

Boland said he programs on a PC. He uploads those to the company's server and then downloads the needed program at the machine into the same software used for creating it.

Although the toolmaker's previous CNC grinder accommodated 24 grinding arbors while the latest one accommodates only five, Boland said having a larger wheel magazine has benefits but is more temperamental and less predictable than the current one. Each arbor accepts up to three wheels, but, depending on the grinding path, two wheels typically are loaded on an arbor.

The 325linear is much more reliable and "seems to be more solid" than Crowley Tool's past CNC grinder, Boland said. But when an issue does arise, remote diagnostic capability on the machine's CNC enables the Schütte team to "look inside" the machine while it's operating to gauge performance, resolve issues in-process and even make suggestions to the operator about how a particular cutting sequence might be improved.