Membrane Pressing Pays Off

 

Northern Contours has 12 years of membrane pressing experience. As the company's business has grown, it has branched out into non-traditional thermofoil markets.

On the surface, manufacturing membrane-pressed components seems easy enough.

Machine a substrate, typically MDF, on a CNC router, spray it with adhesive, put the component onto a tray, put the tray into the membrane press, press the button switch and let a combination of heat and pressure work its magic.

But as most any company with membrane pressing operations can attest, there is more to the process than meets the eye. Mastering the art and science of membrane pressing should not be taken lightly nor should someone, on a whim, get into pressing. It takes much more know-how and financial resources - especially during start up - than might be imagined.

Temperature and pressure settings, adhesive selection, batch size and foil types are just a few of the variables that factor into producing a quality product on a membrane press.

As two companies, Northern Contours of St. Paul, MN, and U.S. Customized Finishes of Suwanee, GA, have found, advancing through the membrane press learning curve requires no small amount of trial and error. But the pain has not been without gain. Each of these companies has carved a solid business niche, first in the manufacture of one-piece cabinet doors and drawer fronts, before branching out into other product types like mouldings, office furniture and closet components. And each of the companies has been featured in Wood & Wood Products' WOOD 100 Report of fast-growing woodworking companies.

Following are separate accounts of these membrane-pressed component specialists.

Northern Contours

Northern Contours started in 1992 with just two CNC routers and one membrane press. That is a far cry from the 16 routers and 12 membrane presses - from Wemhoner, Shaw Almex and Globe - the company now operates at its Minnesota facility. In addition, Northern Contours runs a second component operation in Corbin, KY. Sales reached $42.8 million in 2003 and were expected to surpass $47 million last year.

Such mercurial growth is not only a testament to the increased popularity of membrane-pressed components, but to Northern Contours' ability to adapt to growth. Keeping up with the heightened demand for its components has required more than merely investing in new equipment. Northern Contours has had to improve its scheduling system and manufacturing flow to more efficiently juggle an increased volume of custom orders within its 140,000-square-foot facility.

National Sales Manager Larry Skow says the company used to have a logjam of work-in-process throughout the plant. "When we start (a specific order now), we finish it as soon as reasonably possible within the plant, rather than having a bunch of different products floating around. Our processing time to complete an order went from a couple days to a couple hours."

Much of the increased efficiency was gained at the CNC router operations. Instead of using twin-table routers, Northern Contours recently invested in nested-based routers. That investment has paid off because one person can operate two routers rather than two people operating one, as in the past, Skow says.

As far as membrane pressing is concerned, Northern Contours President Mike Rone says, "The advent of the pin press" has been a big benefit to advancing his business. The pin press eliminates the use of spoil boards for elevating substrates about 5?8 inch above the bed of the press so that the thermofoil can be formed around each of the components to reach the melamine back.

Sensors read the size and shape of a part and signal for the required combination of pins to support it. "All we have to do is place the part on the tray and the press takes care of the rest," he adds.

Rone is the first to admit that his last statement is overly simplified. While the pin presses have proven more efficient than the spoil boards they replaced, Rone says there are many other variables that must be factored into the equation to be successful.

"This includes how you arrange the parts on the press tray to issues with press pressure and heat that lead to poor bond and delamination problems," Rone says. "A lot of variables have to be in the right range to make sure everything comes out the way you want."

Temperature plays a huge role in the quality of the finished product. Rone says press temperature must be maintained at a constant level at all times to reactivate the glue for proper adhesion. Because it can take three to four hours to ramp up the operating temperature of a press that has been turned off, Northern Contours instead lowers the press' temperature settings during weekends. By not shutting the presses off, they can be ramped up to operating temperatures in about 90 minutes, Rone says.

Rone notes it also is important to make sure the press heats evenly and that the substrate is not placed on the press cold - a point of particular concern during Minnesota winters.

Northern Contours regularly performs tests not only to assure the quality of shipments to its customers, but also to find ways of improving the overall process. For example, through testing, the company found that it is critical that components not sit too long after adhesive is applied to them. Thus, often times within 28 minutes or less of being sprayed with glue, parts are loaded into the membrane press for processing, Skow says.

For all these issues and more, Rone suggests companies would be wise to leave membrane pressing to the experts, unless they have sufficient volume to run the machine all day, every day.

"There are companies that have gotten into it, but can't run it full-time. They can't keep enough product going through it to be efficient," Rone says. "It's not an easy operation to start and stop. It's not like a saw. The idea is how many times can the press be filled in an hour with parts. That's where the productivity comes from."

U.S. Customized Finishes

U.S. Customized Finishes was incorporated in 1991 offering unpainted, painted and primed MDF doors and parts. The company added membrane pressing in 1996 and has since learned how to maximize use of the machine, in the process opening a new product line of thermofoiled doors, drawer fronts and other components.

U.S. Customized currently operates a Shaw Almex membrane press at its 25,000-square-foot facility.
Phillip Clark, company owner, says, "Our original offering required many persons, as well as days and weeks of processing time, to complete these products. After an MDF panel is sized and routed into doors, it can be thermofoiled and ready for shipping within a matter of hours, allowing us to produce more parts with fewer people.

"Trends were headed toward thermofoiling because it offered a cost-effective, durable product," Clark adds. "Also, the white-painted-door trend was giving way to cherry and maple hardwood."

Like its counterpart to the north, U.S. Customized had to overcome the learning curve of the membrane press. With considerations such as adhesives, temperatures and substrate materials, the company found that learning the intricacies of the press could be a cumbersome trial-and-error process.

Once its operators became more familiar with the press, U.S. Customized began to optimize the machine's potential.

"We are lucky to have operators who have worked here many years and can use their experience to optimize the trays," Clark says. "We are a custom shop and we try to optimize the press space as much as possible."

Clark notes, "A custom job will take longer than pressing 200 pieces of the same size and color." In the event the company has a job consisting of only a few doors and drawer fronts that will not fill the 40-inch by 97-inch tray, then it also will try to run some stock mouldings or drawer fronts to fill it.

The press has turned into a workhorse for U.S. Customized and is used all day, every day to foil doors, drawer fronts, mouldings, desktops, etc. All U.S. Customized doors and products are machined in-house on a pair of SCMI CNC routers. MDF mouldings are manufactured on a Weinig moulder.

"Thermfoiling allows for reduction in labor, yet provides higher production levels at the same time," Clark says. "This process has a quicker lead time for our customers" versus painting.

While U.S. Customized has thrived with its press operations, Clark, like Rone and Skow, says start-up costs can be expensive for both equipment and inventory.

"You have the initial cost of the machine that can be depreciated over time," he says, adding, "In order to offer a variety of products, a substantial investment must be made in maintaining an inventory of foils, board stock, glue, etc."

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