Zero-Point Clamping Speeds Setup: Productivity

Sometimes the idea for a workholding solution takes some time to implement. That was the scenario at A to Z Machine Co., said Marc Manteufel, manufacturing engineer and IT manager. The 29-yearold, employee-owned CNC machine shop has 11,150 sq. m. (120,000 sq. ft.) spread over three buildings in Appleton, Wisconsin, where about 135 employees work during two shifts.

For a long-term job machining a part made from austempered ductile iron for the defense industry, the shop was using a pin-based system for clamping fixtures for about six years, Manteufel noted. With that system, a 20 mm (0.787″) pin went through a receiver alignment bushing in the fixture plate into a receiver bushing in the base plate. “Then you have a thumb screw that you have to crank down.”

He added that there were eight clamps, or pins, on the fixture plate, and the operators had to unclamp the pins, clean them, change the fixture plate and line up the bushing holes so they could insert the pins every cycle. Not only did each changeover consume about 10 minutes, but the process was also physically awkward. “They were reaching up and over the fixture to get at the back pins, so ergonomically it was not very pleasant for them.”

Manteufel said he had known about zero-point clamping for years and decided he wanted to implement it with the fixture the company makes. He did an extensive amount of online research to learn more and then contacted a couple of distributors he has worked with who connected him to tooling representatives. After considering various systems, A to Z Machine turned to Lyndex-Nikken Inc. in Mundelein, Illinois, for a zero-point clamping system manufactured in Germany by Zero Clamp GmbH.

“The features of the product stood out from the competition,” he said. “Mechanically, it seemed a lot more sound and simpler. I wanted something that I felt was going to last trouble-free.”

Manteufel noted that the system from Lyndex-Nikken has a full contact collet like a drawbar on a machine tool. A low amount of air pressure pumps up an internal diaphragm and expands the die spring plates, which pulls the collet back. The collet clamps when the air pressure is removed.

“There’s just a lot more contact, so there are no concentrated points for wear,” he said. “Nobody else had anything like that at all.”

In addition, rubber seals between the clamping segments prevent dirt, coolant, moisture and other debris from entering, Manteufel added.

Because only one type of clamping stud, or retention knob, is required, the Lyndex-Nikken system beat the competition when it came to simplicity of operation, according to Manteufel. “Because their tapered ring on top that locates is able to expand slightly and then radial float ever so slightly, it takes up any difference in length measurements between the pots. You do not have different style knobs to worry about.”