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ESA Manufacturing and Trim Specialties Inc. is the exclusive Tier 1 manufacturer of interior plastic parts for AM General's civilian Hummer vehicles.

ESA's ATV Fabrication Business 'Humming' Along

ESA finds there's nothing 'hum'drum about manufacturing the interior components for the civilian Hummers.

By Karen M. Koenig

Business is humming at ESA Manufacturing and Trim Specialties Inc. As the exclusive Tier 1 manufacturer of interior plastic parts for AM General's civilian Hummer vehicles, the Williamston, Michigan-based thermoformer has forged a unique path to success.

ESA's initial involvement with AM General came about through its work as a sales rep for another company. When that other company decided to stop producing parts for AM General in 1994 and concentrate on its core business, ESA President Brad Ebersole said the company saw it as an opportunity to diversify its product line, expand its capabilities and also further its relationship with the automaker. The only problem was, ESA had no prior experience in the thermoforming portion of the business.

"But AM General fully supported us. We had never let them down before, and we guaranteed we wouldn't do it to them now," reflects Ebersole on that time. "We got the authorization in November, and by Dec. 17, we had signed a lease on a building. By Jan. 7, we were in full production."

ESA's first thermoformers were single station Maacs with 212-foot by 3-foot shuttles. In addition to supplying the machines, Ebersole says the company also relied on Maac Machinery to train and educate the ESA employees in all aspects of thermoforming.

ESA Manufacturing and Trim Specialties Inc. is the exclusive Tier I manufacturer of interior plastic parts for AM Gerneral's civilian Hummer vehicles. These parts include: the upper and lower A and B pillars, center windshield sets, rear windor sets, kick panels, instrument panels, dashboards, front console panels, door interior panels, gear shifter panels, glove compartments, plus the horn button.

ESA's Manufacturing Capabilities

Today, ESA is a full service thermoformer with added capabilities in vinyl wrapping, trimming, assembly, engineering development and support.

The company uses a cell system for manufacturing parts in its 30,000-square-foot plant. ESA's 30 shop employees work in groups composed of: trainees, middle level personnel (basic knowledge of machine processes) and group leaders (experienced operators).

Cut-to-size material is purchased from sheet extruders and shipped directly to the company. Although ABS and HIPS are the primary materials used by ESA, the company also machines: acetates, acrylic, acrylic/PVC, butyrate, polycarbonate, polyester, HDPE, polyethersulfone, propionate, polypropylene, polysulfone, rigid vinyl and rigid foam vinyl.

"We've set up a strategic alliance where we work with one primary plastic house, one primary vinyl house and one primary house for foam," Ebersole says. In keeping with its just-in-time philosophy of manufacturing, the company will typically place a blanket "number of pounds" order for materials from its suppliers and then order the exact number of "bundles" a week prior to production. "We have an average run of 40 to 60 parts, so having the material in 50-piece bundles works well for us," Ebersole says.

Production is constant at ESA, where a single job often involves a multitude of parts. For the civilian Hummer (aka the Humvee), ESA manufactures from high-temperature, high-heat grades of ABS the: upper and lower A and B pillars (front and rear interior frames), center windshield sets, rear window sets, kick panels, instrument panels, dashboards, front console panels, door interior panels, gear shifter panels, glove compartments &emdash; even the horn button.

All parts are thermoformed on one of six machines. In addition to the two single-station Maac formers, ESA also has a 4-foot by 6-foot Maac rotary and two Lamco rotary formers: a 4-foot by 6-foot and a 6-foot by 10-foot with platens adjustable via CNC.

After the automotive interior parts are formed, excess material is manually trimmed. The parts are then sent to one of two Motionmaster CNC routers equipped with carbide tooling for close tolerance trimming and drilling of holes. All waterjet and laser cutting is currently outsourced.

"We really promote our state-of-the-art, real-world thermoforming capabilities. But what really makes us unique, strong, is our capability to do vinyl wrapping," Ebersole says.

Vinyl-wrapped components are first hand sanded to remove any nubs which can telegraph through the vinyl skin. Next, small "vent" holes are drilled through the plastic substrate to allow any air to escape during the forming process, thus ensuring a tight bond with the vinyl skin.

Timing plays a critical role in the next phase of the process. There is only a few minutes leeway between the time when the plastic substrate is first sprayed with a 3M heat-activated adhesive and the adhesive sets. Within this narrow window of time, the machine operators must insert the substrate into the rotary former, allow time for the vinyl to heat to the optimal temperature and then program the machine so that the vinyl forms correctly onto the plastic substrate.

Up until a few months ago, ESA also did all the back wrapping of the vinyl, a process which Ebersole says is a very labor-intensive. It now works with another Michigan-based company and subcontracts out that portion of the job.

(ATV+SUV) x luxury=Hummer

AM General's Hummer is a deluxe 4x4 with a luxurious ( $60,000 to $100,000-plus) price. Designed to withstand a variety of temperatures and terrains, the Hummer's exterior, heat-treated aluminum alloy body panels are bonded together then riveted, similar to an aircraft's construction. The interior panels are thermoformed and machined from high-temperature, high-heat grades of ABS by ESA Manufacturing and Trim Specialties, which then vinyl wraps the components under strict quality control guidelines.

A luxury ATV priced between $60,000 to $100,000, the civilian Hummer features heat-treated aluminum alloy body outer panels, with interior components made from ABS. ESA is the exclusive supplier of the Hummer's interior plastic components.

Designed for the adventurous driver, the vehicle has 16-inches of ground clearance, steep angles of approach (72°) and departure (37.5°), and a Central Tire Inflation System, allowing the driver to simply flip a switch on the dashboard and adjust the tire pressure while on the move to adapt to the various terrains.

Other features of the Hummer include: its low center of gravity, 130-inch long wheelbase, 72-inch track width, 37-inch tires and TorqTrac 4 technology which monitors the rotational speed of each wheel "to automatically reduce tire spin on severe terrain or slippery surfaces by applying the brake to the spinning wheel, allowing the differential to redistribute torque to those wheels with traction."

The Hummer is available in five models: two-door hard top, four-door hard top, four-door open top, four-door wagon and four-door slant back.


Diversification pays off

Although manufacturing components for the Hummer continues to be the majority of ESA's business, Ebersole says he would like to expand into other markets.

"We're trying to diversify so that we don't have to worry about cyclical markets or interest rates.

"During our first two years, 100 percent of our business was for AM General. Today, it's more like 70 percent. Although the Hummer is pretty recession-proof, I'd like to see us bring in other business so that that figure is down to 30 percent," he says.

Some of that business is coming from other auto makers such as Navistar, for which ESA has manufactured items such as access doors for fuse boxes, or through specialty jobs, such as the barrier walls and trunk dividers ESA has designed and manufactured for police cars of nearby area city departments.

As a Tier 2 supplier for the marine industry, ESA has fabricated dashboards, shifter panels and glove boxes.

"We also manufacture a variety of items for the craft industry. We'll develop the molds and make models for stained glasswork, or the molds for light boxes like Tiffany lamps," he explains. Diamond Tech International is just one of the companies for which ESA manufactures plastic molds and parts.

For the office supply industry, ESA has contracted with Deflecto to manufacture literature holders out of HIPS, which are then sold through retail outlets such as Office Max and Staples.

"We've even done specialty items like theft-proof mailboxes," Ebersole adds.

Maintaining quality control

Quality control is an important part of ESA's successful manufacturing philosophy. While group leaders maintain the general manufacturing standards within their individual cell areas, an ESA quality control engineer conducts a part's inspections at every station every 20 to 30 minutes.

"Some might think that's excessive. But a production run might have a 40- to 60-part cycle, so it may only be in the machine for two hours total. If you inspect less than that, you might not be getting a good sample," Ebersole says.

Of the three full-time quality control engineers, one remains on the shop floor at all times, conducting inspections at the various work stations. Another checks measurements on parts with a Faro arm and keeps control of the paperwork, while the third QC engineer "orchestrates the big plan," Ebersole explains. A Macbeth Judge II is also used in-house to ensure color consistency on parts from one job order to the next.

Maintaining a high level of quality control goes hand-in-hand with ESA's goal of earning QS 9000 and QS 9002 certification. Ebersole says the company expects to earn both certifications within the year.

ESA Manufacturing and Trim Specialties Inc. now has a Web site promoting its custom and high production design, engineering and manufacturing capabilities. highlights ESA's ability to manufacture "everything from items that are little or big, easy or hard. We want to show that we're not pigeonholed into one market," says Brad Ebersole, company president.

Although the majority of the products manufactured currently are for the automotive market, ESA is also a Tier 1 and Tier 2 supplier to the marine, craft and office supply industries.

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