Tooling Article



Toolroom Takes a Front Seat for Investment at Mitchell Metal Products

By: Brad Kuvin

Tuesday, March 1, 2011
Toolroom technology part 2
Behind every great pressroom is a great toolroom, equipped and staffed to move new dies from the design center efficiently through production, and to also return production dies requiring maintenance back to the presses in a timely manner. Toolrooms also are tasked with supporting assembly and welding operations, by manufacturing jigs and fixtures.We interviewed managers at three metalforming companies to learn how each is equipping its toolrooms to be the perfect partners to their production-manufacturing operations. Part 2 of 3.
A trio of new projects completed since 2008 have allowed Mitchell Metal Products, a Merrill, WI, metal stamper and fabricator, to maintain machining as an inhouse core competency. The impetus came a few years ago when new company management recognized the need to increase stamping-press capacity, to improve its ability to compete on larger stampings and tooling. Its realization came as it sought to increase activity on its newest mechanical press—a 400-ton model from Blow Press, acquired in 2004, with a 48- by 96-in. bed and 32-in. windows. Before that acquisition, press capacity topped out at 150 tons.

“That Blow press is at capacity now, and we’re in the market for a new complementary press to further increase our capacity,” says company president Tim Zimmerman, who along with two others acquired Mitchell Metal Products in 2008. “Immediately after we took over the company we focused on beefing up our tooling department,” he adds, going on to describe three major projects that fit that charge.

Software Upgrade Becomes Job One

“First, we married our SolidWorks CAD programming to 3D QuickPress three-dimensional tool-design software. 3DQuickPress is a SolidWorks add-on for progressive-die design that allows our designers to more efficiently develop strips and then detail the dies,” says Zimmerman. The software includes feature-recognition technology and provides a knowledge base for springback and bend allowance.

“The project reduced our timeline from die design to build by 30 percent,” Zimmerman estimates. “We’re saving anywhere from a few hours on a simple blanking die to several days when developing complex dies.”

Next Up: Surface Grinding

After tackling design, Zimmerman set his sights on improving die-making efficiency by looking to upgrade to new grinding and machining technology. Late in 2009 a new automatic surface grinder landed in the company’s toolroom, which has proven so productive that the firm has been able to decommission two aging manual grinders yet expand capacity to allow it to bring outsourced grinding work back inhouse, an immediate savings of $25,000/yr.

“The beauty of the new surface grinder (a Chevalier FSG-2040ADII model) is its

Three-axis milling on Mitchell Metal Products'
Three-axis milling on Mitchell Metal Products’ new Milltronics CNC machine.
ability to automatically dress the wheel between passes,” says Zimmerman, noting the desire to run as lean as possible in the toolroom. The 63-employee company staffs its toolroom with seven machinists.

According to Chevalier specifications, the operator can set the dress amount from 0.0002 to 0.0008 in.; dressing passes across the wheel from one to four; and dress frequency during rough and fine grinding. “This allows the machine to run unattended,” adds Zimmerman, “reducing our machining costs.

“We used to outsource as much as 10 percent of our tooling work,” Zimmerman continues. “Increasing our toolroom capacity (with the new surface grinder, as well as a new three-axis milling machine) has allowed us to bring all of our work inhouse, in particular larger-format tools for the Blow press. Our die-build costs have dropped by $150,000/yr. as a result.”

Milling Last But Not Least

The three-axis milling machine Zimmerman speaks of came to MMP late in 2010, just in time for the company to take advantage of the Section 179 deduction and the bonus depreciation rules. It’s a Milltronics VM 30 model (56- by 24-in. table) that also allowed the company to bring back inhouse the large-format die machining it had been outsourcing. Among its features:

• Automatic lubrication

• Spindle cartridge-cooling system

• 15-hp closed-loop, two-speed spindle motor

• Spindle options to 15,000 RPM

• 1000-in./min. rapid traverse

“That 400-ton stamping press is a high-use resource for us, and if we need to get a die out of and back into the press in a hurry, inhouse machining offers us the best to do that,” says Zimmerman. “We’re more flexible and responsive in the eyes of our customers, an absolute necessity as we look to grow and succeed.”

Grow and succeed describes exactly the path on which MMP finds itself. With its newly

New Milltronic VM 30 model vertical machine
Investing in this new Milltronics VM 30 model vertical machining center has allowed Mitchell Metal to bring back inhouse the large-format die machining it had been outsourcing.
expanded toolroom capacity as its backbone, the company now has the capacity to design and build as many as 90 dies/yr., says Zimmerman. “We’ll build twice as many dies in 2011 (50 to 55 new dies) as we did in 2010, and we’re also ramping up production in the toolroom with new fixtures to boost our robotic-welding capabilities.”

MMP added a new Panasonic robotic-welding cell in 2007 and recently updated it with new gas-tungsten-arc-welding (GTAW) technology which, says Zimmerman, “is opening up new doors for us. The new GTAW equipment has greatly improved weld quality compared to gas-metal-arc welding, which many of our customers have become excited about. So our toolroom, in addition to supporting the pressroom, is busy supporting our robotic-welding operations with new jigs and fixtures, as well as building test gauges for our quality-control department.”

People Power

Of course expanding the toolroom’s capacity and its abilities—to work on larger dies as well as design and build welding and assembly fixtures and jigs—takes more than just technology. The toolmakers need to communicate and understand the needs of the various production departments—“welding, for example,” offers Zimmerman. “Our designers and toolmakers worked hard to better understand the unique requirements of the robotic welding cell, areas such as how the robot needs to access each weldment, what works best in terms of fixture design to allow the line workers to quickly and accurately move the welded assemblies into and out of the jig, etc. All of this has to be accounted for in the fixture design.

“We’re also taking our toolroom workers out to visit our customers,” Zimmerman continues, “to learn how we can better design our dies and fixtures to help the customers achieve their goals related to end-product form, fit and function. It all starts in the toolroom.” MF


See also: Blow Press Limited, 3D Quick Tools Ltd, Chevalier Machinery, Inc., Milltronics Mfg. Co., Inc.,

Related Enterprise Zones: Other Processes, Tool & Die

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