A Solid Choice

Basics of solid surface materials and their fabrication, and why shops are adding them to their product lines. July 20, 2002

Reprinted with permission from Modern Woodworking.

Cabinet shops are adding solid surface to their product lines

By David Welch

As the 21st century opens, solid surfacing will continue to get plenty of attention in the wood products industry. With certification from a solid surface supplier, a typical cabinet shop can increase its margins by 20 percent and offer a higher-end product. Modern Woodworking interviewed industry sources to find out what makes solid surface such an attractive material for cabinetmakers and what are some tips for effective fabrication.


The solid surface industry is growing at 25 percent per year, according to figures from the ISSFA.

Michael Wilson-South was the owner of a cabinet shop until introduced to the world of solid surface fabrication. South’s shop was making cabinets for a 52-house project in his homestate of Hawaii, where he owned a small family cabinet shop. He realized he had significantly underbid the project.

“We were working fifteen hours a day, seven days a week, trying to get the job finished on time and we knew we weren’t going to make any money,” South says. “Just as we were wrapping up installation, someone came in with pieces of Corian®. There were no drop edges or fancy decorative edges on them. He dropped them down on top of the cabinets, put silicon joints between them, set the splashes and left. He made more money for that than we did for the hours or work we put in on cabinetmaking.”

That incident left an impression on South. A few years later, a Corian® dealer approached South and offered him a fabrication opportunity. South accepted the opportunity and has not made cabinets in 15 years.

“I did both for a little while. I had the cabinet shop and I was fabricating solid surface, but I was making more money on the countertops than the cabinetry. Generally, the countertops and cabinets can cost the same in an average kitchen. The material cost is a little more for solid surface than for cabinets. Cabinets ran about thirty percent of my job cost and solid surface ran between forty and forty-five percent.

“The profit margin for the countertops is greater than the margin on cabinets primarily due to labor. However, I didn’t get out of cabinetmaking for financial reasons, but because I found the product (solid surface) good to work with. It’s very much like woodworking. It allows you to be creative because of the seamless nature of the product. There are hundreds of colors and you can make great designs within it and leave no seams behind.” South is now president of Solid Surface Technologies.

Because of South’s story and many more like it, the solid surface industry is growing at a 25 percent per year clip, according to the International Solid Surface Fabricators Association.

“Those figures are based on surveys that we conducted with DuPont, Formica, Wilsonart and other major suppliers,” says Sandy Milroy, director of communications for ISSFA. “The great thing about solid surfacing is that the same tools that work with wood can be used to work with it. That is why so many wood product manufacturers get into the product because they already have much of the capabilities. The majority of our members started out as cabinet makers.”

Interest in solid surfacing has grown so much in the cabinet industry that the ISSFA has begun offering classes to train cabinetmakers how to fabricate. “We actually have a fabrication school that we are in the process of developing here. We have presented our first fabrication courses on repair techniques and inlay techniques.”

Just over a year ago, the International Solid Surface Fabricators Association announced plans to build the ISSFA Training and Education Center in Henderson, Nevada. To date, the ITEC has received over $350,000 worth of tools donated by associate members such as AXYZ Automation, Colonial Saw, Norford Industries, Timesavers, Auto “V”- Grooving and Fein Power.

Most woodworking shops are equipped to fabricate solid surface
Before one can fabricate and install solid surface, you first must be certified by the supplier. This process can require the fabricator to travel to classes at the facilities of the supplier, or some suppliers will send training personnel to the prospective fabricator.

Certification is required because of some early failures of woodworkers to fabricate solid surface properly. “Solid surface is fabrication sensitive and we found that too many woodworking shops treated it as another sheet good and did not pay attention to the rules of fabrication issues,” says John Huzway, manager of fabrication services at Fountainhead.

“We offer accreditation for kitchen cabinet manufacturers who wish to use our product in countertops. However, it is different when we get into ancillary uses of solid surface, which I feel will become greater than the kitchen industry in time. These uses are so diverse and different that we handle certification for millwork houses on pretty much a case by case basis. In other words, they will submit drawings and we will audit them, red line them and give them a statement if need be saying that we will back their fabrication.”

Most woodworking shops are well equipped to fabricate solid surface. Some are even more equipped than shops that specialize in solid surface. “Many woodworking shops have a post forming machine that we have discovered can be used like an oven to heat and thermoform the material,” says Huzway. “A lot of fabrication shops that do not do woodworking cannot thermoform because they aren’t equipped for it.”

The differences in the two operations become apparent in the tooling used for machining as well as the gluing and the sanding processes. The gluing process is fairly unique to solid surfacing in that it parallels acrylic fabrication, according to Huzway.

In sanding, there is a progression of grits to be used, but it is specific for each brand of material. “DuPont will have different specifications from Wilsonart, which are different from Fountainhead. It is basically a common sense practice. The sanding process usually includes the use of micron film and Scotchbrite® pads and varying grits depending upon what kind of finish is requested by the end user,” says Brad Reamer, president, Wilcor Solid Surface.

The difference in machining solid surface and machining wood is the need for carbide tooling. “Solid surface is much harder than wood,” says Reamer. “You are dealing with a plastic resin and the filler is an ore filler, a metallic derivative.”

Dani Homrich, president of Dani Designs, feels the vertical panel saw is the most important tool in his fabrication process. “It is an important machine because you don’t have to move the material to cut it and you are able to cut angles. A flatbed panel saw is too hard to move material. A vertical panel saw is the number one purchase of a six-man shop,” he says.

Homrich also recommends a v-groove machine for fabrication. “For anywhere from $1,800 to $3,500, depending on the model of the panel saw you buy, you can buy an attachment to do v-grooving. If you are only going to v-groove one top a day, there is about a twenty minute changeover time. The only disadvantage of using a panel saw to v-groove is that you first have to cut your sheet and then change over to do your v-grooving.

“If you are going to do more than one top a day and you are going to run a v-groover for more than two hours a day, three times a week minimum, then I would recommend using a stationary v-groover. It is more cost effective that way. You are talking $40,000 to $80,000 for a stationary v-groover. If you don’t have a panel saw, you need one to use a v-groover anyway. You cannot get true enough cuts on a table saw.”



What is solid surface?
Solid surface is an acrylic material manufactured into flat sheet panels and designed for use in interior and exterior applications. It is suitable for a wide variety of residential and commercial applications including kitchen counter tops and bathroom vanities, restaurant table-tops and work surfaces, hospitality areas, healthcare, banks and other corporate environments.

Solid surface sheets may be bonded to each other to create a continuous, seamless surface that is suitable for both horizontal and vertical use.

Most solid surface materials combine two main ingredients: a natural mineral, which serves as the filler, and a resin, which serves as the binder. These are combined and then cast in a curing process that results in a sheet or a shape.

The most common mineral is alumina tri-hydrate, or ATH. ATH is a refined form of bauxite ore and can comprise up to 75 percent of a sheet of solid surface. Bauxite is a form of clay.

ATH is chemical and stain resistant, water-resistant, fire resistant, translucent and is hard enough to give impact-resistance, but soft enough to be machinable.

Other materials have been used as fillers for solid surface. Calcium carbonate glass fibers and even recycled newsprint have all at one time been used as fillers.

Two main resins used in the manufacturing of solid surface are acrylic and polyester. A purely acrylic-based resin yields a sheet that is thermoformable. It can be heated, bent into a new shape and cooled without any loss of performance characteristics.

Polyester resins, including those that are mixed with acrylic, are used in demanding or high strength applications. With the addition of a catalyst, usually peroxide, the sheets are then cast and cured.

Casting of solid surface consists of mixing the resin with fillers and additives. The mix is poured into an open mold. Occasionally, molds are closed for products with shape. In casting, air bubbles should be avoided by either adjusting the viscosity of the mix or vibrating the casting table. Air bubbles in the material cause voids once the material is cured.

Some solid surfaces cure in the open air. Steam or ovens are sometimes used for curing. Many polyester resins require a heating-cooling cycle after curing, which increases the degree of cure. An improperly controlled cure can cause air bubbles appearing in the material, which effectively ruin it as a solid surface. Carefully controlling temperatures during curing is an effective way of reducing this risk.

Features and benefits
• Durable: resists chipping and cracking and retains its beauty
• Renewable: scratches, cuts and burns can be sanded away
• Available in classic solid colors and versatile patterns
• Homogeneous composition for color and pattern retention throughout the thickness of the sheet
• Offers seamless, one-piece appearance
• Stain-resistant and easy-to-clean
• Nonporous and hygienic: dirt can’t be trapped, liquids won’t penetrate, bacteria and fungi won’t grow

Limitations


• Solid Surface is a mineral-filled material and, like natural materials, some slight color variation may exist from sheet to sheet. For optimum color matching, some suppliers will provide sequentially numbered sheets to be used in a single installation.
• Solid Surfaces are designed for interior and exterior applications, however, this material is not recommended for applications that may require prolonged exposure of the surface to temperatures above 175°F.
• Although Solid Surface is stain resistant, some chemicals - including acetone, strong acids (such as concentrated sulfuric acid), chlorinated solvents or strong solvent combinations like paint remover - can stain or damage the surface. The extent of the damage will depend on the length of contact.
• Solid Surface is not recommended for use in photographic processing laboratories.


Installation guidelines
When working with solid surface products, it is important to remember that the fabrication techniques used will affect the appearance and performance of the finished installation. Training, which specifically addresses solid surface fabrication and installation, is recommended.

Proper conditioning of the solid surface sheets, along with other materials being used in the assembly, will minimize shrinking or expansion of the final installation. Ideally, all components should be conditioned at 70° to 75°F and relative humidity at or below 45% for 48 hours prior to installation.

Corner joints should be made square rather than mitered. This minimizes material usage and facilitates installation. To prevent stress cracking, seams should be placed at least 3” (76.2 mm) away from any corner or cutout.

All joints should be reinforced with a 4” (101.6 mm) wide strip of solid surface material and supported by framing. Joint edges should be straight, smooth and clean. To minimize the potential for stress cracking, exposed edges of the reinforcing strip should be chamfered.

For cutouts, use a router equipped with a sharp 3/8” (9.5 mm) diameter (minimum) carbide bit. The corners of a cutout must be rounded to a 3/16” (5 mm) radius and smoothed on both top and bottom. Inside corners require a smooth 1/2” (13 mm) radius. Larger radii are recommended whenever possible.

Solid surface is compatible with many commercially available caulks and sealants; however, a specially-formulated solid surface adhesive is required for making joints, repairs or custom edges.

Install countertops on perimeter framing support (without added substrate), using small amounts of silicone sealant.

Sheets of solid surface may be installed vertically over suitable substrates such as marine-grade plywood, water-resistant gypsum board and ceramic tile. Neoprene-based panel adhesive or white or clear silicone may be used. DO NOT USE WATERBASED ADHESIVES.

The recommended expansion clearance with uncaulked solid surface sheets is 1/32” (.8 mm) for every 8’ length. Joints to be caulked should be approximately 1/8” (3 mm) wide to allow for caulk penetration and expansion.

Reprinted with permission from Modern Woodworking.