Killing setup time

Author Cutting Tool Engineering
Published
May 01,2011 - 11:15am

Related Glossary Terms

  • collet

    collet

    Flexible-sided device that secures a tool or workpiece. Similar in function to a chuck, but can accommodate only a narrow size range. Typically provides greater gripping force and precision than a chuck. See chuck.

  • coolant

    coolant

    Fluid that reduces temperature buildup at the tool/workpiece interface during machining. Normally takes the form of a liquid such as soluble or chemical mixtures (semisynthetic, synthetic) but can be pressurized air or other gas. Because of water’s ability to absorb great quantities of heat, it is widely used as a coolant and vehicle for various cutting compounds, with the water-to-compound ratio varying with the machining task. See cutting fluid; semisynthetic cutting fluid; soluble-oil cutting fluid; synthetic cutting fluid.

  • cutting force

    cutting force

    Engagement of a tool’s cutting edge with a workpiece generates a cutting force. Such a cutting force combines tangential, feed and radial forces, which can be measured by a dynamometer. Of the three cutting force components, tangential force is the greatest. Tangential force generates torque and accounts for more than 95 percent of the machining power. See dynamometer.

  • feed

    feed

    Rate of change of position of the tool as a whole, relative to the workpiece while cutting.

  • inner diameter ( ID)

    inner diameter ( ID)

    Dimension that defines the inside diameter of a cavity or hole. See OD, outer diameter.

  • straight oil

    straight oil

    Cutting fluid that contains no water. Produced from mineral, vegetable, marine or petroleum oils, or combinations of these oils.

  • tolerance

    tolerance

    Minimum and maximum amount a workpiece dimension is allowed to vary from a set standard and still be acceptable.

  • toolholder

    toolholder

    Secures a cutting tool during a machining operation. Basic types include block, cartridge, chuck, collet, fixed, modular, quick-change and rotating.

  • turning

    turning

    Workpiece is held in a chuck, mounted on a face plate or secured between centers and rotated while a cutting tool, normally a single-point tool, is fed into it along its periphery or across its end or face. Takes the form of straight turning (cutting along the periphery of the workpiece); taper turning (creating a taper); step turning (turning different-size diameters on the same work); chamfering (beveling an edge or shoulder); facing (cutting on an end); turning threads (usually external but can be internal); roughing (high-volume metal removal); and finishing (final light cuts). Performed on lathes, turning centers, chucking machines, automatic screw machines and similar machines.

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END USER: Highland Products Corp., (440) 352-4777, www.highlandproducts.com. CHALLENGE: Reduce setup time when employing high-pressure coolant for Swiss-style machining. SOLUTION: A through-coolant Swiss-style toolholder that directs coolant over the insert to the tool/workpiece interface. SOLUTION PROVIDER: Streamliner & Associates Inc., (814) 440-1548, www.streamlinertools.com

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Effectively delivering high-pressure coolant to the tool/workpiece interface when Swiss-style machining improves chip control, extends tool life and helps impart a finer surface finish. 

To achieve those benefits, Highland Products Corp., Mentor, Ohio, was making 4"- to 6"-long external tubes from 3⁄16" steel brake line as part of a high-pressure coolant system for its machines. The system delivers straight oil at pressures from 500 to 2,000 psi when needed, noted Matt Nolan, the company’s plant manager. The Swiss job shop produces part volumes from one to more than a million for industries including medical, aerospace and automotive.

IMG_5531.tif

Courtesy of Highland Products

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Courtesy of Streamliner

Streamliner through-coolant Swiss-style toolholders, which direct coolant over the insert to the tool/workpiece interface using a dovetailed distribution plate, reduced setup times and extend tool life at Highland Products.

To control line output, Highland tapped the tube ID to insert a nozzle. “To make a new tube takes 20 minutes—if you’re good at it,” Nolan said. 

The line also required bending to precisely position coolant flow. “That takes some finagling,” he added, noting that the approach was effective but prone to incorrect line positioning and lines being bumped out of position. In addition, changing a tool required moving the line out of the way and then repositioning it for the new tool.

Several years ago, the shop tested through-coolant tooling with two distribution ports, one down the tool face and one from the side, to effectively deliver coolant while reducing setup time, but elected to continue fabricating its custom lines. “It didn’t seem to offer much,” Nolan said about the product.

Then, about a year ago, Rolf Kraemer, owner of Streamliner & Associates Inc., Edinboro, Pa., dropped off literature at Highland about Streamliner’s through-coolant, Swiss-style screw-on insert toolholders that direct coolant halfway over the insert—about ½"—using a dovetailed distribution plate. Although the coolant stream gathers some air, it is significantly denser than coolant coming from a nozzle, and denser coolant extends tool life, according to Kraemer. (Streamliner also produces through-coolant holders for non-Swiss applications.)

After examining Streamliner’s tooling, Nolan indicated that he liked how the coolant inlet design enables flexible placement in a machine as well as the toolholder’s ease of use. For example, each holder has a dowel pin underneath the head that butts against the tool block. After a user indexes an insert, which requires removing the holder from the machine, the pin quickly and accurately relocates the holder when reinstalled.

Shortly after Kraemer delivered the first holders, Highland was running a new job that involved a relatively free-machining material, a large DOC and applying flood coolant. The cutting force exceeded the main spindle collet’s gripping force and pushed the workpiece material back in the collet, causing parts to be out of tolerance, Nolan explained. Rather than turning slower and reducing the feed rate to achieve the required part specifications, the shop decided to try a Streamliner tool and apply high-pressure coolant. 

“We didn’t change anything except that toolholder and it totally eliminated that push-back scenario,” Nolan said. “I called Rolf the next day and said, ‘I’m good; we’re sold.’ ”

Nolan attributed the improvement to accurately directed high-pressure coolant creating a freer cutting condition. For the application, tool life tripled.

Since then, Highland has purchased additional holders and now has about 20. “We are phasing them in,” Nolan said. “For any repeat job that employs high-pressure coolant, we are switching to Streamliner tools.”

Streamliner offers three basic distribution plates with orifices of 0.094", 0.188" and 0.250" and a plate without an orifice, enabling users to customize the coolant passage. To maintain a high-pressure flow, Highland uses the largest size to maximize coolant volume when coolant is delivered from one of four lines and selects a smaller size when performing simultaneous operations.

With the Streamliner toolholders, Highland Products is significantly reducing setup times, increasing insert life overall about 20 to 50 percent and imparting finer surface finishes—in part by avoiding coolant from an external line knocking a chip back onto the finished product. “With increased tool life, product variability decreases,” Nolan said. “We definitely have a more stable process.”