Derek Korn joined Modern Machine Shop in 2004, but has been writing about manufacturing since 1997. His mechanical engineering degree from the University of Cincinnati’s College of Applied Science provides a solid foundation for understanding and explaining how innovative shops apply advanced machining technologies. As you might gather from this photo, he’s the car guy of the MMS bunch. But his ’55 Chevy isn’t as nice as the hotrod he’s standing next to. In fact, his car needs a right-front fender spear if you know anybody willing to part with one.
There are advantages to having a single operator tend multiple machines and/or performing other tasks while a machine is making chips. However, if the operator isn’t aware that a machining cycle has been completed, the machine could potentially sit idle for an extended period of time. This can be especially true when jobs have long cycle times.
One shop came up with a simple solution to prevent this from happening, and it offers the solution to others facing similar situations. Produced by C&C Manufacturing, the “Short Stop” wireless device minimizes machine downtime by alerting a machine operator that a machining cycle has been completed.
The video above shows how it works. After a cycle has ended, a Short Stop transmitter is installed in the machine’s spindle. The machine moves the transmitter to trigger an actuator button that sends a signal to a receiver that is located somewhere near an operator to alert him/her that the cycle has ended.
When not being used, the transmitter can be stored in the machine’s ATC magazine like any other tool. Its circuit board is coated to prevent damage due to vibration during changeout and its housing is sealed with an o-ring. The transmitter can also be moved from one machine to another as needed.
Tool vending systems like this one can enable shopfloor supervisors to help operators find out why tools are breaking or wearing sooner than expected.
3D Medical Manufacturing, the medical job shop profiled in this article, is currently on its second iteration of a tool vending system: a system from MSC Industrial. This system enables the shop to accurately track every nondurable tool for each job while providing daily tool usage reports for those jobs. This enables tight cost control and ensures that the shop never runs out of the tools it needs, which was a problem in the past that led to extended machine downtime and high next-day shipping charges. The vending system automatically reorders tools once a specified minimum inventory level is reached, and the shop’s tool crib manager reloads the tools when they’re delivered.
However, this system also serves as an important problem-solving device. Each job has a maximum number of tools that an operator can pull. The system locks out operators who attempt to pull a tool beyond that limit and notifies a supervisor of the situation. That way, the supervisor can work with the operator to determine why tools are breaking or wearing sooner than expected. In some cases, the operator can precisely explain the problem, meaning a change to the process might be warranted. In other cases, the operator might be unsure of the problem. Therefore, the notification turns into a teachable moment, because the supervisor can help the operator pinpoint the issue and remedy it.
The shop also has expanded this concept to its inspection devices, some of which are supplied by customers. This eliminates time wasted looking for special gages, for example, and ensures accountability for those devices.
The cam-actuated system shown in this video is one alternative for automated workpiece installation/removal on the new S11 cylindrical grinding machine. Note the in-process gaging capability being demonstrated, too.
I’m often introduced to new machining equipment at trade shows or company tech centers. Last week, United Grinding unveiled its high-production Studer S11 cylindrical grinding machine for small parts to members of the press and UG distributors at its “Mini Motion” event held on the USS Yorktown aircraft carrier docked in Mount Pleasant, S.C.
In an effort to make it easier for busy manufacturers also to see the machine in action, the company is bringing it to them via a tour that includes stops in eight key areas across the United States as well as Canada and Mexico (tour dates and cities are listed below). UG engineers will be available at each stop to answer questions about the machine and the applications it’s geared toward.
The S11 occupies only 19.4 square feet of floor space but still includes a large 19.7-inch-diameter (500-mm) wheel.
It’s important to note that the S11 was not developed to be a universal-type grinding machine. Instead, it was specifically designed for automated, high-volume production of small, precision parts as long as 7.87 inches. The machine weights approximately 5,000 pounds and features a Granitan mineral-casting bed that offers good vibration damping qualities. It accommodates a 19.7-inch-diameter (500 mm) wheel and is available with the wheelhead plunge angle set at 0 or 20 degrees. It can also be set up to perform high-speed peel-grinding operations. Like other Studer cylindrical grinding machine designs, the X and Z axes are part of a self-contained cross-slide unit. Both axes have linear guideways mounted on roller bearings.
The S11 features a streamlined designed without unneeded options and uses no hydraulics. Instead, component actuation is performed electrically or pneumatically. Compact size with a floorspace area just over 19.4 square feet is combined with easy access for maintenance and setup. The main door offers three opening stages. Stage one opens upwards minimally and is intended for quick manual loading or a brief check of the workpiece. For stage two, the door opens a bit more so all table-mounted accessories are accessible from the top. Stage three enables a lower front panel to be dropped down to make the front fully accessible during set ups.
The machine is available in a range of automation configurations, and users should consult with UG representatives to determine the configuration that’s best-suited for their application. One is shown in the video above, in which a simple but effective cam system is used to remove and install workpieces from the chuck. StuderWinFocus software was developed for this machine to enable pictogram step-by-step programming, and the Siemens Sinumeric 840D SL control with touchscreen interface has a tablet look to it.
Here’s a list of cities and dates for the S11 North American tour (click here to register). The machine will be accompanied by the Walter Helitronic Mini-Automation system that combines a five-axis universal grinding machine with robot loader.
• Feb. 19-20—Greer, S.C.
• Feb. 26-27—Rochester, N.Y.
• Mar. 5-6—Brecksville, Ohio
• Mar. 12-13—Livonia, Mich.
• Mar. 26-27—Itasca, Ill.
• April 8-9—Woodbridge, Ontario, Canada
• April 22-23—Los Alamitos, Calif.
• Spring 2014—Queretaro, Mexico
The Mini-Motion event was held on the USS Yorktown, which was appropriate given the journey the S11 machine is about to embark on. While touring the USS Yorktown, I was able to check out the aircraft carrier’s machine shop. Most machines there are still functional, and I appreciated the sign at the shop’s entrance.
If you’re in the process of training somebody to be a machine operator who has limited or perhaps no shop experience, have them check out this video. The guy does a really good job of conveying a good deal of information related to the basics of how to attack a machining job (cutter selection, chip load, determining speeds/feeds, etc.). He calls it a brain dump, but it’s more helpful than overwhelming.
Some have asked for more time to participate in our “Top Shops” benchmarking survey, so we’re extending the deadline to complete the online survey to Friday, February 28.
Participants who complete the survey will be able to receive a series of summary data reports of the results. Participants are also encouraged to enter the Top Shops Honors Program by providing their full contact information at the beginning of the survey.