COUNTERTOP CHOICES
traditional & modern
Whether the material they’re selling is soapstone or stainless steel, quartz or laminate, online storefronts focus on the glossy “after” images. Rarely do they tell you how the countertop of your dreams is mined or manufactured, shaped, and precision cut. A major wave of technological innovation has swept the countertop fabrication industry, so much so that CNC (computernumeric control) is beginning to filter down to the hobbyist level. You yourself probably won’t be using CNC to outfit your kitchen with countertops, however. Countertop production is still challenging, highly skilled work, requiring sophisticated and powerful machinery. In addition, most materials still require hand finishing, if only for sealing and polishing. While manmade materials like solid surfacing and engineered stone are doing a remarkable job of mimicking the look of natural materials, wood, and even metalwork, they lack the hand finishing that gives the timeless, natural materials a sense of continuity with the past.
No matter what the material, fabrication shops make extensive use of mechanized equipment for everything from heavy lifting to machining technologically sophisticated cuts, bends, grooves, and crisp or rounded edges.
stone
Natural stones including granite, slate, soapstone, and marble are quarried in large blocks in locations all over the world. Marble is famously mined at Carrara, Italy, and other sites around the globe. Today’s countertop-quality soapstone comes from Brazil, Turkey, India—and Virginia, where one of the densest and most desirable soapstones, albarene, has been mined for more than 150 years.
Slabs vary in size, but most are between 8' and 9' long, and 5' to 6' wide. Simply moving a marble or granite slab weighing between 600 and 800 pounds into the work zone requires a forklift. For more delicate maneuvering, each precious piece is then picked up and moved either vertically or laterally, using a suspension cable vacuum device hung from a crane. (Suction cups hold the stone in place.) The cable system allows the heavy slab to be angled in any direction until it meets its resting place on the cutting bed.
While there are variations in the methods used from fabricator to fabricator, natural stones including granite, marble, and soapstone, and engineered stone (a category that includes quartz) are cut in much the same way. Most shops still use plywood or cardboard templates made at the installation site to plan the cuts on stone. (Precise measuring means that as much of the slab as possible can be used, minimizing waste.) In a CNC-equipped shop, the physical template is then marked at key points at regular intervals, and the data is then transferred to a CAD (computer-aided design) program. The program draws up the template and transfers the information numerically to the cutting bed, where a
CNC (computer-numeric control) machine will ultimately cut and shape the pieces.
The CNC machine actually visualizes the cuts to be made on the slab, sending a picture back to the CNC operator. Then it automatically selects one of more than a dozen mill blades (cutting heads) with different profiles to make the initial cuts using a wet saw equipped with diamondencrusted blades.
Since all of the initial cuts are sharp, the edges must be polished, either with a CNC milling machine or by hand. Many manufacturers use waterjet machines for curved and angled cuts. The waterjet cuts, shapes, and drills using a high-pressure jet of water mixed with an abrasive material. The amount of pressure and the type of abrasive needed varies depending on the type of stone, its density, and even its color.
All cutting and shaping is done with water, from polishing with abrasive diamond grinders down to hand finishing. That’s because exposure to small bits of silica in the stone can scar the lungs of workers, causing silicosis. “If you do all the cutting wet, there is no dust,” says Roger Teixeira, a soapstone dealer and fabricator in Glen Rock, N.J. Even so, he encourages his workers to wear protective masks at all times.
Installation and fitting is often part of the work order. A good fabricator will custom-fit the pieces of stone onsite, join seams with color matched two-part epoxy, and make any necessary adjustments. At least one soapstone fabricator, Vermont Soapstone, cuts countertop and sink pieces to rough measurements in the shop, then does all the final cuts, shaping, and fitting onsite, using a pop-up fabrication shop.
BUTCHER BLOCK
Since its early use in the 1870s, butcher block has been a versatile work surface in the kitchen. Unlike flat-grain or plank wood tops, butcher block is formed from strips of hard maple, oak, or another hardwood glued and pressed together, then turned so that the hardest, most durable grain surfaces (either edge grain or end grain) form the cutting surface. Since even tightly grained wood is vulnerable to water penetration, butcher block is sealed with a food prep-safe oiled finish.
Building a butcher-block counter begins with careful selection of the wood. Lumber is sorted by grade, then air- and kiln-dried. Once the lumber comes into the fabrication plant, it’s planed and sanded to create a flat, smooth work surface. Next, it’s run through a rip saw that cuts the wood into rails that are a consistent 1 ¾¾ "x1 ". To make edge-grain countertops, premium rails are laminated and glued together side by side, forming a solid piece of butcher block where the wood grain lines run in linear fashion along the rails.
Making end-grain butcher block literally requires turning edge-grained butcher block on its head. Laminated edge-grain boards are glued and stacked on top of each other, then placed in a
screw press, which squeezes the wood and glue together. After drying, the block is set on end so that the end grain of the rails faces up as the work surface.
steel STAINLESS
(and the increasing rare, nickel-based Monel) have been in use in the kitchen for well over a century. Easy to bend and shape, stainless steel is a superb surfacing material for counters and sinks. “One thing about metal, you can integrally weld everything together,” says Jeff Subra, owner of Specialty Stainless in Buffalo, N.Y. “You can’t weld a sink into quartz.”
Steel fabrication has its own set of specialty machinery, usually including punch or shear machines and press brakes. The machines can be hydraulically or pneumatically powered, or CNC-controlled. At Specialty Stainless, all of the cutting and “nibbling” is done on a CNC punch machine. A flat sheet of 16-gauge steel is placed on a pneumatic hydraulic table where the punch machine cuts out holes for sinks, faucets, and soap dispensers.
The countertop then goes to a CNC press brake, which tools the metal using a punch and die setup. The edge of the sheet is placed in the machine by one or two workers, then quickly crimped all along the edge. A simple bend, like a 90-degree right angle, may require only one “hit” on the machine. The more complex the curve, the more bends. The skill comes in knowing how to position the sheet and where to place it for subsequent bends.
Seams and corners are formed up using TIG (tungsten inert gas) welding, which reduces the emission of sparks. Sinks are hand-formed rather than punched, and surfaces are hand-peened to make radius edges. Once the sink is formed up, all welds are ground and polished by hand. “We hand-build all our own sinks,” Subra says. “The metal thickness stays true because it isn’t stretched or stamped.”
Unlike stone and wood surfaces, stainless steel requires no sealer. When polished, it forms a film that gives it antimicrobial properties. While stainless steel arrives at the factory with a standard polish, Specialty Stainless does custom finishes such as its antique finish: a dull, random finish similar to matte nickel or pewter.
Stainless Specialty also works in copper, zinc, and aluminum. Subra notes that copper has become almost prohibitively expensive; zinc will not last nearly as long as steel because the zinc top coating eventually wears away if not maintained; “stainless steel can last indefinitely.”