| Paolo Chiezzi, vice president of Makor USA Inc., says most customers request a profile sander that is both versatile and flexible. |
| THE BASICS OF BRUSH SANDING |
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The prep is very important to the moulding, as uniformity in the stain color comes from this prep. The prep is a uniform sanding of the top surface of the whole moulding. The top and the bottom of the moulding will get the same sanding, and by doing this, the same uniform stain color is achieved. Brush sanding mouldings in this way prepares the moulding, not just for the staining, but also for the next step, namely the sealer coat. When the sealer coat is applied to the moulding, the pre-sanding with a moulding sander has made sure that no sharp edges are on the moulding. This does not mean that the brush sanding distorts the profile, it only means that knife-sharp edges are slightly broken. The rules are that a sharp edge will not be able to absorb very much stain or sealer, and thereby this point would be very weak and a possible place where the homeowner would breach the sealer coats and expose raw wood. To make the edges as strong as possible, a light break is performed in the raw wood sanding so the stain and sealer coats sit better on those edges. After the stain and sealer have been applied and the moulding has dried, the brush sander is now ready to do sealer sanding on the moulding. The speed of the spindles is reduced for a softer sanding, and a speed of up to 50 feet per minute can be reached for sealer sanding of the mouldings. The machine can be set up with 150-grit for pre-sanding and 220-grit for sealer sanding. Any grit from 80 to 320 is available for the brush sander. Special sanding applications like a rustic, antique or Southwest look also can be achieved by using steel brushes or stiff tynex brushes. The brush sander will take care of bottlenecks in the production of mouldings as finish sanding and sealer sanding are now easy tasks to do. Information provided by Sand Tech Inc. |
Selecting the Sander
When a new contract means having to create something that is new to the company, it is very important to have machines that are capable of adjusting to that change. Chiezzi says that the first things a customer asks for are versatility and flexibility.
“Those are the features most often requested by customers when purchasing profile sanders,” Chiezzi explains. “Obviously, this is due to a different approach to the market by customers who have to join the lean production philosophy in order to improve production efficiency and reduce storage. This just-in-time production requires frequent changes of batches.”
The versatility and flexibility that are so important in a profile sander can come from a variety of features.
“The most important feature on a profile sander is variable speed on the brush heads and the use of different style abrasives with the same machine so you are not locked into one style of abrasive,” says Malherbe.
“What if one day you want to do rustic sanding? The company you are buying a profile sander from needs to have that abrasive covered too,” he adds.
“The customer needs to match the degree of sanding required and the complexity of their mouldings to the profile sander configuration,” says Williams. “For example, to remove knife marks, profile sanding belts are always required. For a light de-nibbing or buffing, one can use abrasive wheels or brush-back wheels.”
All agree that as sanding technology advances, machines become available which will better integrate with other equipment, while improving quality and providing users with an increased level of control.
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Profile sanders are an important piece of equipment for any job involving linear moulding. Photo courtesy of Lobo Machinery Corp. |
Changing the Face of Sanding
With increases in fuel costs, as well as increased competition, many companies are looking for ways to do more with less. Advances in computer controls and the ability to work in a lean environment have shaped the direction of profile sander design.
“Profile sanders can now be incorporated into smaller, more modular machines in order to match the lean manufacturing concept,” says Williams. “Rather than having an eight- or 12-head sander to sand all of a given customer’s profiles, we are now seeing production divided up into smaller, more efficient work cells. This allows for the sander to be configured for a specific moulding, and the manufacturing is then accomplished in a lean, just-in-time manner.
“Customers realize the premium they pay for space in their factories, so they are looking for modular equipment with a reduced footprint,” he adds.
With machine size decreasing and modularity increasing, end users also are looking for machines that have a quick set-up time, Williams adds.
Improved CNC capabilities also have become a factor in profile sanding. The controls allow users to have a greater command over the speed, functionality and precision of the machine.
“Electronics make it possible to realize machines with computerized control of all functions and monitoring of the working parameters,” says Chiezzi.
Profiles sanders also are seeing improvements in the abrasives used. According to Malherbe, brush sanding is becoming more widely used, with sandpaper acting as a back up for more aggressive sanding. Robin Yuan, sales manager for Lobo Machinery Corp., agrees, saying a variable speed for type of grist of sanding wheel or disk is important. Yet, despite these advances in the machinery, a profile sander is only as good as the maintenance it receives.
Long Live the Sander
As with any piece of industrial equipment, proper maintenance is critical to proper functioning and extending the life of the machine.
Just as with any other machine on the shop floor, breakdowns mean mounting costs to the company, not only in repairs, but in lost time and bottlenecks as well. A proactive stance on preventative maintenance can go a long way in extending the life of any profile sander, as well as significantly reducing the chance of a machine failure.
“The same type of periodic maintenance that is required of any industrial machinery applies to sanders,” says Williams. “A good dust extraction system will prolong the life of the abrasives and allow for better, higher-quality sanding for a longer period of time.”
Chiezzi concurs, adding that planned maintenance at the hands of highly skilled engineers is essential. “Based on this, it is possible to avoid inaccurate troubleshooting, especially when the breakdown requires stopping the line. An improper repair can cause serious damage to the machine,” he adds.
Malherbe agrees, saying, “monthly maintenance of the drive system and blowing off the machine daily” are important. Yuan adds that it is important to the use right speed and revolutions per minute for the various pieces that are being put through the machine.
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As more companies turn to lean manufacturing, some profile sanders are becoming smaller to accommodate smaller work cells. Photo courtesy of QuickWood |
As CNC technology becomes more prevalent in profile sanders, users will be able to better control speed, precision and quality. Photo courtesy of Delle Vedove USA Inc. |
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