Precision Thread Grinder Sets New Productivity Standard

Cleveland Gear helped write the book for AGMA (American Gear Manufacturers Association) standards and considered themselves to be precision thread grinding experts.

Because of this, they firmly believed that their present machines were unmatched for precision thread grinding anywhere in the industry. When something happened to one of Cleveland Gear's thread grinding machines, it was not just a routine setback: they had to find an alternative source right away. Their shop could not wait until repairs were made, so they reluctantly shipped their work to a precision thread grinding specialty shop and hoped for the best.

The results from the specialty shop exceeded Cleveland Gear's highest expectations--which led them to ask what kind of thread grinding machines the specialty shop was using. The answer started changing Cleveland Gear's long-held belief of excellence in thread grinding machines. The specialty shop had used machines that were designed and built in the US by Drake Manufacturing (Warren, OH).

The specialty shop's operators had praised the performance of their Drake machines, while Cleveland Gear's experience with their thread grinders was almost the direct opposite: long lead times, frequent breakdowns, slow parts delivery and poor machine documentation.

As a result, a team of Cleveland Gear design engineers, manufacturing people and machine operators met with Drake systems engineers to study the situation. The two groups collaborated to determine Cleveland Gear's specific requirements, then to develop a part-specific software program for a Drake GS:TE (Grinding System: Thread External) 12 X 45 model CNC thread grinder to meet their needs.

John Cruikshank, the Drake systems engineer who developed custom programming for Cleveland Gear's new machine, confirms that, "Cleveland Gear knows thread forms inside and out." He cites the inventory of over 1,500 master worms built by the company over the years, each with specific-purpose geometry. Using a specific "family of parts" program, Drake was able to duplicate all the geometries. Now, a Cleveland Gear operator only has to enter the part variables in the menu-driven, part-specific program.

Cuts Set-Up Time More Than 75%

The first job for Cleveland Gear's newly purchased Drake machine was also one of their most complex--a worm with 10 starts and a high helix. From the beginning, the Drake machine ground to within 0.0002" without any problems, much to Cleveland Gear's satisfaction.

After running the machine 24 hours a day, seven days a week, Brook Trout, manager of Manufacturing Engineering for Cleveland Gear, reports, "There's just no comparison. The Drake is more than twice as productive as our other machine. It reduced set-up time by more than three-fourths and cut cycle times in half."

According to Trout, "In terms of quality, our Drake machine is a whole new level. But, Drake's attention to detail--and willingness to make sure our service needs are met--that's unmatched anywhere." One of Cleveland Gear's machine operators, Wayne Kratzer, cites the following example of Drake's service: "One time, around 4 o'clock on Friday, we had a problem. We needed help right away.

After calling Drake, their technician was here the next day (Saturday) at seven o'clock in the morning. Because of an accident, we needed a new grinding wheel and dresser roll. The Drake technician brought us loaners until we could get our own," he says. "Our previous machine wasn't very well documented," adds Brook Trout. "Our new Drake came with the whole nine yards: a complete set of specification, maintenance, and operating instructions; plus a list of all the suppliers and their phone numbers.

"The bottom line is great," Trout concludes. "Our Drake gives us much more flexibility, precision, and longer life for about a third the cost."