The machine and materials developments over the past 25 years in the woodworking industry have been a marvel to watch, particularly the edgebanders. We have seen machine systems move from manual controls, relay circuits, and mechanical switches to full-blown computer involvement. Refined machine movement control systems are now capable of duplicating all but the most intricate of hand-created work.
Tool manufacturers have produced refined cutters capable of unheard-of feed speeds, even in difficult-to-cut materials, and the material scientists and manufacturers continue to bring about 2,000 new plastic materials into the marketplace each year. Wood and other plant-based materials continue to evolve to create new materials, adding more design elements for product engineers to work with.
Craftsmen have been covering the edges of furniture assembly parts for more than 2,000 years with a wide range of decorative trim materials. Historically, applying edge treatments to panels and rails was a means to cover edge-joint construction methods or hide a less attractive wood material used in the body of the assembly. The procedures were time consuming, labor intensive, and expensive.
In the past 25 years, however, the procedure of trimming the edge surface of any furniture part or assembly has become a highly automated and refined process. It's a process capable of completing thousands of linear feet of production in a single day's operation.
As edgebanders and materials have developed in recent years, an interesting change of direction has taken place. Early on, mass production was the primary operating principal. Ever-higher feed speeds and output capabilities drove the technology to produce ever-larger, dedicated complex machine systems capable of thousands of feet of production daily.
However, in just the past several years, we've seen a dramatic change. Machinery developments are driven now by manufacturing costs and, to a lesser extent, newer marketing strategies. Today, the newest technology provides us with machine systems that are capable of almost immediate changeover and a wide range of tasks. This allows profitable production runs of any length -- from one to thousands.
The basic procedures to secure a decorative edge trim to a furniture part remain largely unchanged, except that the individual tasks are completed in a complex automated machining process. The edge surface is machined to a surface quality to accept a glue-line bond; the adhesive is applied; the parts brought together; the adhesive cured; and the edge material is trimmed and finished.
A broad review of edgebander technology clearly indicates that all of the machining technology developed over the past 25 years is still present -- that is, the first basic mechanized system for attaching a decorative edge trim is still out there nearly in its original form. And among all of the manufacturers, we can see every development that has taken place as the technology has become more refined. The parallel industries that supply edgebanding materials, adhesives, electronic motor and machine control systems, and specially developed cutting tools also contributed in very large ways to what is now in the edgebander marketplace.
The size and variety of edgebanders runs literally from tabletop models for applying preglued edgebanding to behemoth combination double-end tenoner/edgebander systems that can be more than 80 feet long and have 30 or more individual machining stations on each side.
Most machines now common in the marketplace can apply edgebanding to panels or rails varying in thickness from 8 mm to more than 60 mm. The length and width of the workpieces and edgeband materials that each of the machines is capable of applying seems to vary only by what particular market segment each machine manufacturer chooses to pursue. Many units are becoming increasingly versatile, but none are completely so.
The smallest edgebanders are available with several different features relating to simply attaching the trim material to the workpiece. Found among the smallest of machines are fairly refined features including powered feed and part guiding mechanisms. On such machines, the clamping pressure is applied manually while the workpiece is guided past the feed rollers.
The use of preglued trim strips is more popular among the small machines, although a few of them do have glue application systems for limited production.
Throughfeed edgebanders for small shops or short production runs can have any of several individual task capabilities, and can be either single- or double-sided. Available features include:
- A means to hold and feed a supply of rolls or strips of edgebanding material;
- a system to control and apply the needed adhesive;
- a refined system for holding and clamping the workpiece during the glue-cure time;
- both leading and trailing edge trimming;
- top and bottom edge trimming;
- top and bottom edge chamfering or softening;
- and sanding, polishing, or scraping of the machined edges.
The small throughfeed machines are limited to straight edgebanding operations. Most can't do corner rounding or shaped edges. There are several small manual or fairly automated edgebanding machines for specialty products, such as edgebanding an S shape.
Applying edgebanding to a radiused shape poses a collection of inherent problems not present on straight panels or rails. What's most bothersome is machining the edge to a quality surface that will be dimensionally accurate and smooth enough to accept a glue-bond line. Any deformation or irregularity in the edge face or top/bottom edge easily telegraphs through the edgeband material and affects the glue bond strength.
Of particular concern with radiused shapes is ensuring that the top and bottom edges are precise and visually attractive. Also, the edgebanding chosen must be somewhat elastic and strong to withstand being shaped into the rounded form.
Many of the largest throughfeed edgebanders are manufactured much as automobiles are in the sense that the basic frame is constructed so most of the available options can be installed without modification. For instance, there are systems that will apply edgebanding to the outside edge of a circle, while others will do the inside. Yet another edgebander will, in a limited way, do aspects of both applications.
The largest machines may be capable of:
- sizing (scoring and hogging off the unwanted offal);
- edge milling for precise straight edges (edge jointing for superior edge quality);
- shaping, for softforming (V-shapes, S-shapes, convex or inlay profiles);
- preheating (wide range of methods and systems);
- profile wrapping;
- end trimming, top and bottom trimming, chamfering, or edge softening;
- solid wood material profiling;
- corner rounding (in a few systems);
- profile or straight scraping;
- and sanding, buffing, and polishing.
The most recent generation of large combination machines joins together the capabilities of a tenoner and edgebander into a continuous throughfeed machining system. The capabilities and controls continue to evolve, expand, and improve, adding CNC controls to every imaginable motor control and machine movement. Many machines include the changeover and setup procedures as a part of their automated processes. A further refinement of combination machines is the ability to deal with a wide range of edgebanding materials, as well as shaped profiles such as softformed or postformed, and inlaid edge details.
The greatest advances continue to be the use of refined electronics and the expanded use of PC-based technology. Many of the current high-end machines have the ability to receive programming or order entry information by being hardwired to remote locations with the use of infrared data transmission systems or barcode scanning software.
The latest technology
The most recent technology in edgebanding machinery doesn't look like any system manufactured before. It looks more like an over-developed CNC router. In fact, it is, but with a vast number of tool change systems and capabilities. At least two or more machine manufacturers are producing these gigantic CNC machining centers that are capable of duplicating the work tasks of several individual complex woodworking machines into a single workstation -- including most, if not all, of the conventional edgebanding operations.
It seems that the two general products that will receive the most attention in the coming months are shaped work surfaces such as desktops and tabletops, and several varieties of manmade flooring. In the past several years, there has been tremendous research directed at developing the machining systems to manufacture these products.
There are more than 20 machine manufacturers producing edgebanders sold in the U.S., and each has features and or capabilities a bit different from the others. But we can make general categories of available machine technology based on features, capabilities, refinements, and cost. What must be done then is to take the time and expend the effort to mate the needs of our product manufacturing with what is readily available to us.
The next logical move is to purchase the machine that will meet our near-future needs, not what is needed to catch us up today. Buying for our future needs really does make good sense.
The first hard lesson a downhill skier learns is to lean forward. It seems like a contradiction of nature's physical laws -- until you fall on your behind.
Getting a Top-Notch Edge
While the mechanization of dealing with the edge treatment of furniture assembly parts began as a means simply to hide some visual aspect, today edges and corners have become more of a visual focal point with shape, size, texture, or color added to the edge with precision and great detail.
The list of materials used as edge trim is almost endless, ranging from solid woods, wood veneers, and wood-based composites, to polycarbonates and the continuously growing collection of plastics.
The manufacturing basis of all edge treatment deals with minute details that must be monitored constantly:
- the surface quality of the edge to which the trim will be attached;
- the makeup, nature, and constant operational condition of the adhesive to be used;
- that the upper and lower edges be free from irregularities, chip-outs, etc;
- the clamping method, pressure, and effectiveness;
- the workpiece's freedom from any deformation, warp, or twist;
- the condition and nature of the trim material;
- and machine adjustments, alignment, and feeding mechanisms.
The list could go on for several more entries, but the overall idea is that preparing a panel or rail part for attaching an edgeband is a painstaking process that requires attention to details as in few other manufacturing processes. There is little if any forgiveness in any portion of the individual tasks involved.
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