TRUE GRIT

It may look like sandpaper, but if you don't like the results you're getting, look again. Do your abrasives require constant change-outs that slow production? Do they clog easily and mar the surface of your products? Is the performance of each new disk or belt always consistent with the one it is replacing? Abide by these three rules of modern sanding technology and success is sure to follow, leading manufacturers say.

Mike Walker keeps an open mind about new products. You never know when you'll find something that can improve production. So the fabrication shop supervisor for Bartimaeus by Design (Thomasville, NC) was willing to try a ceramic abrasive used on belt sanders. The salesman told him it was a higher grade than the 40-grit zirconia belts he was using; and it would last longer. If the claims were true, the manufacturer of aluminum table and chair legs would save a lot of money.

Fortunately, Walker only bought one belt: The ceramic abrasive put a smooth finish on only 10 parts before it broke and had to be replaced. That's a far cry from the 35 to 40 parts his crew can finish with one zirconia belt by Klingspor, an abrasives manufacturer that Walker has favored for nearly 11 years.

Walker laughed when he recalled the experiment. It wasn't the first time he had agreed to try a new product.  But he knows from experience that very few abrasives can meet the high standards demanded by his company: a consistent high-quality polished finish on all products, including stainless steel; and the durability that allows uninterrupted production.  "Everything we do must look good aesthetically because very few parts that we make are hidden. It's all out in the open. Since we do a lot of polishing of stainless steel and aluminum, we go through a lot of different sanding grits in order to get it ready to polish before we send it out the door.  It's all about looks," he says.

It's all about money, too. Poor quality abrasives that require constant change-outs slow productivity, dampen morale and, therefore, can take a significant bite out of profit. So when the accountants at Bartimaeus are crunching numbers, they're more than willing to pay a little more for abrasives that reduce down time. "It costs a little more, but in the long run we save money," remarks Walker, adding, "our current quick-change flap discs are designed to make rotations and change-outs speedy."

When Walker signed on with Bartimaeus by Design about three years ago, he was the only guy in the fabrication shop. Now he supervises nine other employees who use a variety of abrasives, such as discs, wheels and non-woven belts. Also, since most products must be hand-sanded, the firm buys sheets of hand-pad abrasives, which can be cut to size. It was only recently that the company acquired time-saving automated equipment that can be used on some, but not all, products, many of which are health-care related components: mechanisms for recliners, fold-out assemblies for hospital chairs, as well as legs for tables and chairs.

"We brush a lot of stainless steel – tubing or flat-stock sheets, explains Walker. "We're not that big, but we're using a lot of grinding product. People don't like to see welds, so we must go in and make it look like it's grown together naturally. There's a lot of cutting off of welds and grinding. All of it is done by hand."

Despite the tough demands, Walker says his abrasives are always consistent and predictable: Each grit is rated during the manufacturing process, and tolerances are necessarily kept tight.  For example, if the grade of 100-grit sandpaper varies even slightly from one lot to the next, the user of that product may see significant differences when trying to polish a surface.  Grit grades must be exact and predictable so that firms like Bartimaeus can trust their products will meet quality standards.

Sizing is another important quality-control issue. Consider a disk with a 5 in diameter. If the abrasive is even 1/8 in smaller or larger, supervisors like Walker will notice problems in production. If the disk is too small, the rubber backing from the disk sander might be exposed and leave streaks on the surface of the product.  If the disk is too large, the abrasive might gather around the edges of the sander and gouge surfaces. And these imperfections may not be noticed until the product is supposedly ready to ship.

Although clogging of abrasives is generally thought to be a woodworking issue, it can be a problem with some metals, such as brass, bronze and soft aluminum. The clogging begins with some abrasives because a great deal of static buildings up during the sanding process. One solution, by Klingspor, relies on anti-static strategies that include a so-called "open coat" process. By maintaining space between grit clusters, resins (from wood) or metal shavings and/or dust naturally fall away rather than adhere to the abrasive. This allows a shop's dust collection system to easily remove particles from the environment. Also, a stearate, which acts like a dry lubricant, is applied to all abrasives to discourage clogging.

"I know how many parts I can get out of each belt," states Walker. "The consistency is so good I can't tell where somebody changed the belt in the middle of the run. I even use the stuff at home for auto body work. And I used the abrasives in my previous jobs in the aeronautic industry."

Like any new enterprise, Bartimaeus by Design is always on the hunt for new business. The firm has already outgrown a new addition to its plant. But each new product line creates challenges for Walker, who does not have the luxury of ordering large lots of new abrasives for a small or limited run. So he uses a strategy that he calls "lean management." He orders only what he needs as he needs it:  If that means one belt for a short run on a new item, that's all he orders. As a result, his overhead is quickly paid for and he's not stuck with a storage unit stocked with costly amounts of unused product.

"We don't have a lot of overhead because we don't stock material. I order it, it gets cut, we polish it and it goes out the door. The same for sanding supplies. I order four or five times per month in small quantities.  Abrasives come in, product goes out, and money comes in.  It cycles quickly, which is the key to our success," he adds.

Some abrasive suppliers demand that their customers place large orders. But that's not the case with Klingspor. The 100-year-old supplier not only services small orders but can guarantee speedy delivery due to the many distribution points it has worldwide. "A lot of places will only let me order by the case, and you can spend thousands of dollars to buy it when you only need one belt. But with my current supplier the service is outstanding. However I want it, that's how they'll send it, and the delivery arrives within days."

The North Carolina-based manufacturer of industrial-quality sanding and grinding products is also an innovator. The company was the first to develop and produce grinding discs and cut-off wheels for high-speed use. They also developed the abrasive flap disc, which replaced both fiber and grinding discs. This history of achievement is important to Walker, who is eager to learn about any new development that might improve the efficiency of his team.

"If it makes the job faster and easier and brings down the cost – even if the product is more expensive – I'm all for it. And my company has never encouraged me to go somewhere else. They like the product because they like the results they're seeing."

Douglas Glenn Clark is a technical writer based in the Los Angeles, CA.

Klingspor Abrasives, 229 W Bonita Avenue, San Dimas, CA 91773-3010, 909-305-0788, www.klingspor.com.