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Postformed edge not just for countertops anymore.

Postforming technology has been around since the 1950s but its popularity only began to take off with the advent of new applications in the 1970s. No longer just for countertops, it is used for a variety of products from kitchen cabinet doors with a European look to an assortment of furniture and fixtures.

After decades of being relegated to countertop use, the postformed edge, especially the rolled 180-degree edge, has become more popular on wood products ranging from Euro-style cabinet doors to store fixtures and furniture -- products that were once part of an edgeband-only market.

Postforming, or the bending of a decorative laminate over a radius using heat and constant, even pressure to bond the laminate to the panel, has been around since the '50s. It was not until the 1970s, however, that its use began to expand to products other than countertop edges and covings.

The popularity of the postformed look is definitely growing, said C. J. LoBianco, business manager for laminate products at Nevamar Corp. of Odenton, Md. In the past 10 years, the use of postformable grade laminates has increased at a "gradual and fairly steady" pace, said LoBianco. To meet this demand, laminate suppliers such as Nevamar introduced new lines of postformable grade laminates in a variety of colors.

There are a number of reasons why this look has captured the fancy of consumers and product designers. Walter Rohrbach, owner of Edgetech Inc. of Bloomington, Minn., and a 20-year veteran of the postforming industry, said two reasons the smooth edges' popularity has grown is that it is safer and cleaner. "A smooth edge is cleaner, doesn't snag clothes and is safer. If you slip and fall near a countertop or table, wouldn't you rather fall on a rounded edge than a sharp edge?" Rohrbach said.

According to Art Betterley of Art Betterley Enterprises of Blaine, Minn., a 47-year veteran of the laminate industry, architects and designers are asking for the postformed look more often because of the look and because they stand up to a lot of punishment.

"Any woodworker that doesn't postform is losing work," said Betterley, "because there are a lot of jobs that he just can't bid on."

Many woodworkers have begun wrapping their products' edges to get these jobs. Some woodworkers enter the postforming arena so they can offer the soft edge as a value-added service to customers. Still, others who previously bought postformed components from outside vendors bring postforming capabilities in-house to have better control and flexibility of the product. "Most people who come to us for postform equipment have been buying doors and countertops from someone else and all of a sudden they realize they have had no control over what they are buying," said Bob Perez, president of Evans Machinery Inc. of Glendale, Ariz. "Their suppliers are only offering them certain colors and while you may be able to order different colors, it might take time and it will cost more money."

While the woodworker may have more control by bringing postforming capabilities in-house, he should weigh the pros and cons of purchasing the equipment and materials compared to buying preformed countertops and cabinet doors from specialists.

Over the years, suppliers of postformers have worked to enhance their product by upgrading their postforming machinery and through value-added services such as operator training and technical support.

About the machinery

According to Kenneth Holley, president of Midwest Automation Inc. of Minneapolis, Minn., there are two categories of postforming machines. The first group is comprised of "static" or stationary machine and the second type is made up of automatic-feed through machines.

Static machines hold parts in place with the heating platen moving around the part or where the part is rotated around the heating platen. This type of postformer is best suited for postforming one-of-a-kind or short run pieces, Holley said.

Rod MacDonald manager of R.A. MacDonald Co. of Oceanside, Calif., said that a small shop could get the wrapped look without sacrificing time or speed with a machine of this type. "A small shop can wrap one edge in about one minute and that is a complete wrap. You can't even start self-edging by hand in that time and then there is the routing and filing that comes after that. There is no comparison for speed."

According to Holley, production time on a static machine is measured in cycle times. He said it takes about three minutes to complete a cycle -- load, heat, postform and unload a panel. Double that time if the part needs both sides postformed because the postformer is only a one-sided machine.

The automatic-feed through postformer is geared more for companies that produce high-production and repetitive profiles. On these machines speed is indicated in feet per minute and the average production speed for this type of machine is between 10 and 40 fpm, Holley said.

A component manufacturing company is a good example of a shop that might use the automatic feed-through machine, said Phil Herzog, product manager for Homag/Stiles Machinery of Grand Rapids, Mich. "We had a customer on the West Coast who is a component supplier but hadn't previously postformed," Herzog said. "But he saw this as a growing area and thought this would be a good way to introduce a value-added service for his customers."

Information is the key

Whether the woodworker is purchasing a postformer or a piece of hardware, information is the key to making the correct purchase. When a woodworking company begins looking to buy a postformer it must be armed with certain questions as well as being ready to answer questions asked by the suppliers.

Some questions the woodworker should ask include: the sizes and thicknesses of materials that can be formed, how long the machine is, the speed of the machine, the ability of the machine to make a 180-degree wrap, and price, MacDonald said.

In addition, the woodworker should be prepared to answer a suppliers' questions. The answers to those questions would help determine whether the company needs to buy a static or an automatic feed-through machine as well as influencing the types of adhesives (contact, PVAc, hotmelt, etc.) that should be used.

Jerry LeVan, Northeast sales manager for Stefani Group America of Greensboro, N.C., said, "What we will need to know is what kind of product the company is going to postform and how much of the product will be made. The amount you are willing to spend, material you are going to be using and so on."

Herzog added that while a buyer should look at the cost of making the product versus what it can be sold for, he should remember that "postformed parts typically have a very high value-added perception to the consumer."

Money, of course, is one of the primary considerations when it comes to making any capital investment. The cost of the actual postforming machine ranges from a few thousand dollars for a smaller machine geared to custom work to hundreds of thousands for high-production automatic feed machines. Larger machines have a typical payback period of a year or two, said LeVan. Payback for the smaller machine is fairly quick -- some suppliers say the machines pay for themselves with one job.

"We have sold quite a few machines to companies that had always farmed out their cabinet doors to somebody else," Perez said. "Let's say a company gets a large contract, in practically every case after they have bought the machine, bought all the laminates and all the substrates and everything else, they can still make a profit and have the machine on top of it."

Betterley said that "at one time you had to buy real high-priced machines to postform but that is not true today." He said that many woodworkers tack on the price of the machine to their first job to pay for it.

What adds to the cost of postforming is the ancillary machines that are needed, especially if a shop has not worked with laminate before. In addition to the equipment needed to laminate, including a press or pinch rollers, adhesive spray applicators and trimmers, the company will also need a double-end tenoner or some type of shaper to cut the radius.

One exception to this is the Homag Direct Postformer available through Stiles Machinery. In one continuous process the direct postformer automatically takes pre-laminated panels, cuts the radius and wraps the laminate. This eliminates the need for a double-end tenoner and, if pre-laminated panels are purchased, the need for a laminate press, Herzog said. Unlike traditional postforming which almost exclusively utilizes high pressure laminate, the Homag allows for the postforming of low-pressure laminate as well as melamine, HPL, polyester and veneers, he added.


According to most machinery suppliers, training on a postformer is very simple. "Take the first guy walking down the street and after a couple of 180 degree wraps he will be forming easily," said MacDonald. Even on the larger feed-through machines, operating a postformer can be learned quickly, Herzog said. "For someone who has no experience with postforming there might be a small learning curve," he added. "But we have put this machine into companies who have not had postforming experience in the past, and with the training we provide, the customers are running the machine on their own within a couple days." LeVan suggests that several people in a company be trained to operate the equipment so that in case the operator leaves the company there is someone to step in and operate the machine.

Available machinery

In addition to those pictured in the article, the following is a roundup of additional postformers available on the market. For more detailed information circle the corresponding Reader Service numbers.

Available from Midwest Automation Inc. is the Ultraform Automatic Postformer. The postformer has 90- and 180-degree capability, uses either PVA glue or contact adhesive, and wraps unbacked wood veneer or HPL. The company says it has also improved its trimming and finishing accessories.

The PF-100 manual postformer from Edgetech Inc. allows edging of pieces before and after postforming and the company says geometric shapes can be laminated on the machine. A heat surface rotates around the postformed edge and a cooling surface holds and cools the surface after the forming process.

R.A. MacDonald says its machines can form 1/2-in.-to 6-in.-diameter edges on doors and countertops. Wood veneers as well as high-pressure laminates can be formed and the machine is guaranteed against defects for one year.


A typical postforming operation is a multi-step process that begins with a board being cut-to-size, applying an adhesive to the board and the postformable grade laminate, and then laminating both sides of the substrate, leaving an overhang. Laminating only one side of the substrate, usually particleboard, could lead to warping. In America, the use of contact glue far outweighs that of over glues such as PVAc, but as environmental regulations take effect that may change.

After trimming the edges which will not be postformed, the radius is cut. This is generally done with a double-end tenoner.

According to the experts, shaping the substrate is one of the most important steps in postforming. The edge must be perfectly smooth and blend in with the top. "If there is a ridge on that particular radius," said Bob Perez of Evans Machinery, "the laminate is going to crack. You have to make sure the board is shaped properly. Even if the laminate forms and looks acceptable it is susceptible to cracking later."

The laminate and glue is then heated. Heaters come in a wide range of sizes, and the size of the heater determines the size of the product that can be worked. If you make a six foot top, the postformer must be equipped with a 78-in. heater; a 12-foot top would require a 156-in. heater. In general, the longer the heater area, the higher the cost.

The average forming temperature is 325 F, said Rod MacDonald of R.A. MacDonald Co. "If you overheat the laminate you can blister it," he added. "If it is not hot enough it will crack."

Art Betterley, of Art Betterley Enterprises added that there is a "dwell time" or a period of time of between 30 and 45 seconds, to heat the laminate before it is overcured. Once this happens the laminate will crack so "the faster you form it the better you are," he said.

An easy way to know when the correct temperature has been reached is to use temperature indicators such as Tempilaq liquid of Tempil strips, Betterley said. These strips can either be put on the front or back side and should be positioned at two or three places where you are going to form. When the correct temperature is reached, the stick will melt, he said.

After heating, the laminate is then bent over the radius, and constant pressure is applied until the piece cools down and the bond is made. Pressure can be applied through a variety of methods such as the box method or pinch rollers. Laminate has a tendency to "spring" back into a straight position so it is important the laminate be wrapped beyond the point where the laminate will spring back. This point is known as the springline.
COPYRIGHT 1993 Vance Publishing Corp.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1993, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

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Title Annotation:machines used in postforming
Author:Adams, Larry
Publication:Wood & Wood Products
Date:Feb 1, 1993
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