Getting familiar with edge banding
Getting familiar with edge banding
Wooden desks, wardrobes, kitchen units and other wood finishes have smooth and neat edges that look impressive, thanks to edge banding.
During the manufacturing process of wood, edges are often exposed and look ugly and rough. “An edging should match the surface perfectly in colour and texture, be impact and scratch resistant, UV stable and if in a kitchen environment, thermally stable as well,” comments David Behr, managing director at National Edging.
Edge banding entails applying the edging tape to the edges of the engineered wood. This process is done to make engineered wood look like a solid piece of wood all around. “Edge-banding is used to upgrade or as a finishing to melamine, veneer or surfaced boards. Edging is commonly used within the production of kitchens, office furniture or cased goods furniture,” says Nico Jansen van Rensburg, marketing manager at Upper Edge Products.
In addition to improving the aesthetics, edge banding also protects the wood from warping, which could happen if the exposed chipboard edges get wet or become exposed to heat. Because the wood is protected, edge banding increases the lifespan of the entire wood product in the long run.
Types of edge banding machines
Edge banding is both a process and a machine. There are various edge banding machines available on the market, each with different functions and capabilities. There are different edge banding machines for different for wood production categories such as floor manufacturing, furniture and interior furnishings as well as panel and door manufacturing.
Typically, edge banding machines fall within the R250 000 to R2.5-million mark, however there are both cheaper and more expensive machines outside of this range. Ian Fuchs from Donald Fuchs Machinery says that although all the machines are primarily capable of performing edge banding tasks, the difference lies in the additional features which make the machines capable of performing additional functions. “The machines that cost more have improved technological features and are able to perform edging that looks a lot finer.”
He explains that all machines are automated and require an operator to monitor the edge banding process. What would typically happen is that the operator would insert the edging tape and the board into the machine and then closely monitor the process from beginning to end. There is a roller conveyor that feeds the boards into the machine. Fuchs also elaborates on the different functions for various machines – with each function performing a particular task.
The pre-milling function is ideal for rough surfaces where the pre-millers clean the edges before the edge tape is applied. “Because there is a cleaner surface, it would give a better glue application,” says Fuchs. Corner rounding is another function of the edge banding machines. This function enables the machine to perform edge banding around the corners of the board.
The edge banding machines are also capable of three different trimming functions. The first is end trimming where the machine removes any overhang edging that remains after application. Rough trimming takes place when the top and bottom of the chipboard is cleaned. Fine trimming simply does any additional cleaning to the boards. Scraping is another function which differs from trimming in that any excess glue is removed from the board once the edging has been applied.
In terms of what the South African market looks like currently, Fuchs says that South Africa is leading in terms of cutting and edging – where most customers would purchase a panel saw and edge banding machine together. The panel saw is used to cut the panels to size before they go through the edge banding process. Although South Africa is ahead of the rest of the continent, manufacturers are still cautious in terms of their spending. “The economy is very tight at the moment and everybody is looking at price,” he says.
Mobile edge banding
Mobile edge banding machines make it possible for edge banding to take place outside of the manufacturing facility and on site, which would typically be where the installation would be taking place.
The Festool Conturo KA 65 Plus is a handheld mobile edge banding machine that can be carried around to wherever the edge banding activity is taking place. This machine costs under R100 000, making it ideal for small business who cannot afford the bigger machines. The machine can be mounted on a special table – making it possible for edge banding to be applied on various 45-degree angles. “With that being mounted, you can do 45-degree angles,” explains Costa Stavrakis – end user specialist for Festool at Vermont Sales.
The machine has various components which come in a toolbox called a systainer. “All the parts are kept in a systainer. There is a diagram in the actual box to give you a good indication of where everything goes. You never misplace anything; if something’s missing you know exactly what’s missing,” says Stavrakis.
Operating the machine is easy and requires the push of a button and waiting for the machine to warm up to a certain temperature. This process takes approximately eight minutes. Once the machine is on and ready, the user is guided by an LED screen which tells the user what the temperature is as and when it increases. Once the machine is warm and ready to be used, the operator would simply feed the edging into the roller by either free hand or inserted into a magazine attachment. Once this is done, they are ready to proceed with applying the edging onto the board. The non-scratch pad ensures that there is no damage done to the surface during the edge banding process.
The machine has a compartment for the glue pluck (adhesive) to be used during the edge banding and accommodates three glue pucks. “It works on a unique paste application system for efficient, easy and clean edging, where just the perfect amount of glue is applied to the edging, allowing for no wastage. The adhesive comes in four different colours – natural, white, brown and black,” explains Stavrakis.
With just three glue pods inserted and at a height of 18mm you can do approximately 40m of edging. The Konturo KA 65 is very capable of applying edging from a height of 18mm to 65mm and a thickness from 0.5 to 3mm
Once the edging has been applied, there is sometimes remaining overhang which needs to be cleaned up to give a smooth looking edging. Stavrakis explains that there are two ways to get this done. The conventional way is using a router. The router is ideal for thick edge banding. Another way is using a Festool scraper. “The scraper is used and designed to scrape off all the excess edging to get it nice and smooth.” For a rounded looking edging, the scraper has two contour angles, at a 2mm and 1mm radius. The scraper is not sharp and will not harm the user or damage the surface being edged.
As with most machines, maintenance is critical especially for the machine to last. With proper maintenance, the machines can last anything between 10 to 20 years. On the other hand, poor maintenance of the machine drastically reduces the life span to less than five years.
Dust extraction is an important aspect of maintenance for the machines. As such, it is compulsory that customers buy the machine along with the dust extractors. Another maintenance suggestion is to consider cleaning the glue pot every six months.
Edging that lasts
Sometimes the edging comes off after some time. Fuchs attributes this to humidity. Incorrect glue application temperature is another factor that causes the banding to come off. An example of the incorrect glue application is insufficient pressure on the pressure rollers or if the substrate is not square to the edge banding material when applied. Poor priming, incorrect edge banding shape and too much pre-tension in the edge banding material can also cause the edging to come off.
Another factor that contributes to the edging coming off is when the edging is in direct contact with heat. “The placement of appliances such as your kettle and stove hobs needs to be taken into consideration as most EVA based adhesives do not react well with moisture and high temperatures,” says van Rensburg. He also explains that because edges are primed on the reverse or adhesive side, a lack of primer could result in the delamination of the edging. When cleaning any product with edge banding, it is best to use a diluted soap and water mix. “Wipe the edging with a damp cloth and avoid excessive water and abrasive cleaning detergents,” van Rensburg says.
The type of adhesive used during the edge banding process is important to consider. “A very important factor to a successful edge is the adhesion of the material to the substrate. Edge banding machines use either EVA, PUR or Polyolefin hot melts to bond the edge banding material to the substrate,” explains Behr.
Edge banding materials and adhesives
It is impossible to apply edge banding without the relevant materials to do so. Behr explains that there are five types of edge banding materials: PVC (Polyvinyl Chloride), ABS (Acrylonitrile Butadiene Styrene), PP (Polypropylene), melamine impregnated paper and veneer. “All of these are available in a variety of widths, thicknesses, designs and finishes,” he says. He explains that ABS, melamine and veneer edge bandings can generally be coated over if a lacquer or paint finish is required.
Because of their thermal stability and impact resistance, ABS and PP edge banding are the preferred product for use in a kitchen environment. “PP edge banding material requires specific machinery whereas ABS can be applied with your standard machinery,” Behr says. With regards to the adhesive, Behr emphasises that the adhesive used is as important as the edge. “Highly filled cheaper adhesives will show an unsightly glue line and offer an inferior bond.”
Van Rensburg explains that there are two main adhesives used in edge banding: EVA, which has good quality edge-banding glue with sufficient heat and water resistance when applied correctly. The second one is the PUR hotmelt which has superior heat resistance and waterproof when applied correctly.
“The best quality edged panel is generally produced with a PUR hotmelt,” says Behr. He adds that PUR has the highest heat and moisture resistance coupled with the fact that less glue is required than with an EVA or PO hotmelt. “This thin waterproof glue line enables the manufacturer to produce a panel with a zero-glue line.”
Edge banding machinery has evolved over the years. There have also been significant technological improvements which have paved the way for a variety of edge banding machines on the market today. The market for these machines typically consists of tradesmen, furniture manufacturers and shopfitters among others. Whether they are using the big industrial or smaller mobile edge banding machines, careful consideration must be given to using the correct materials and applying the correct techniques to ensure that the edging on the finished product looks attractive and is durable.
By Dineo Phoshoko
Source: Timber IQ