(Written in May, 1999)
by Jim Heaphy
Solid Surface '99, the trade show held in Las Vegas in January, highlighted a wide variety of new products and tools for solid surface countertop fabricators. I commend the International Solid Surface Fabricators Association and its president Jon Lancto for producing such an outstanding industry event. I returned from Vegas with a stack of product literature weighing over ten pounds. I'll spend months researching all the new ideas I ran across.
Because sanding and finishing operations consume such a large percentage of the labor time in the average solid surface countertop job, I paid special attention to new developments in abrasive technology while at the show.
In a workshop called "Finishing and Sanding Techniques" speakers from abrasive manufacturer 3M and tool manufacturer Fein Power Tools offered an excellent overview of the challenges and the very latest solutions. Vince Grlovich of Fein described the basic types of sanding tools available to solid surface fabricators, and explained why the random orbit sander offers performance superior in most applications to belt sanders, orbital sanders and rotary sanders. In the hands of a skilled operator, random orbit sanders offer rates of material removal approaching that of a belt sander, but with much less chance of damaging or overheating the surface. Using the correct sequence of abrasives, they can be used to produce any finish from matte to high gloss, with a high degree of consistency.
To maximize efficiency, it is important to start with the finest grade of abrasive that will begin the job properly. Using an overly coarse abrasive at the beginning just wastes time. When changing to a finer grade of abrasive, wipe the surface clean each time. Random coarse particles scattered over the surface will cause deep scratches that will take extra time to remove. Use an established sanding pattern and stick to it. For example, sand in an overlapping north-south pattern, then an east-west pattern, and then repeat over the entire surface before changing to a finer grade. Expect to spend 45 to 60 seconds per square foot for each step in the process. It is important to follow an established sequence of grades of abrasives proven to be efficient and successful, and stick to that sequence. Don't skip a step.
Some shops prefer to sand dry, while others choose to sand wet. Some abrasives can be used either wet or dry, while others are optimized for one or the other. It is recommended that the first step be dry, to make it easier to visually inspect for large defects. Continue sanding with the coarsest abrasive until all these visible defects have been removed. The advantages of wet sanding are that abrasive disks last longer, the water acts as a lubricant, and it allows for dust control without use of a noisy vacuum. One the other hand, wet sanding can cause messy splashes so many installers prefer dry sanding with vacuum dust control in homes.
At the workshop, I met a fabricator, Paul White of Cache Valley Counter Tops, Inc. of Richmond, UT, who recommended adding a drop of dishwashing detergent to a spray bottle of water when wet sanding. He said that helped the process go smoother.
Tom Boyle of 3M explained the various abrasive grading systems used in the marketplace today, and the characteristics of the different substances used as abrasive particles. He emphasized that a consistent scratch pattern is the key to a good finish. Even a high gloss finish has a scratch pattern - it just consists of scratches too fine to be seen by the human eye.
Less expensive abrasives manufactured with older technologies may be fine for rough work, but their biggest shortcoming is the inconsistency in the size of the abrasive particles. Particles smaller than that called for by the grade are worthless, but those that are significantly larger will do damage to the finish. Every grading system allows for a bell curve of particle size distribution. In the best systems, though, this bell curve is very narrow, with particle size clustered accurately at or near the ideal size.
Four abrasive manufacturers showed new products at Solid Surface '99 that caught my attention. Here's what the manufacturers say about their new products.
One of the pioneers in manufacturing high performance abrasive discs for solid surface fabricators is Micro-Surface Finishing Products, Inc. with their product Micro-Mesh. Featuring a resilient inner cushioning layer and a flexible backing, Micro-Mesh allows the abrasive crystals to cut with a positive rake and an even planing action. The result is a higher quality finish than those provided by fixed crystal abrasives. They now offer their product in two formulations, aluminum oxide for acrylic-based solid surface materials, and silicon carbide for polyester-acrylic blends, either of which will produce a gloss finish in five steps. Call 1(800)225-3006 or go to www.micro-surface.com for more information.
Mirka Abrasives, Inc. has introduced Abralon, which is a thick flexible sanding disk made of an open-cell mesh fabric coated with accurately sized abrasive particles. The mesh is laminated to foam and a cloth backing compatible with hook-and-loop mounting pads. Because Abralon is so pliable, it is especially effective when sanding concave surfaces such as coved splashes and inside solid surface sinks. Abralon is designed to be used wet and is available in six grades from 180 grit to 4000 grit. Call 1(800)843-3904 for more information.
Another approach to sanding coved splashes is offered by Performance Abrasives. Their New Wave sanding discs have a scalloped edge that will roll up slightly when sanding into a cove, rather than digging in and scratching the cove. Their Sand Trap discs have long curved openings for dust collection, rather than the conventional hole pattern. Call 1(800)875-2358 for more information.
The most dramatic new development in abrasive technology is 3M's Trizact film, which consists of precisely shaped pyramids containing micron graded material on a plastic film. As the Trizact disc is used, the tops of the pyramids wear away, continually exposing fresh abrasive material. This ensures a consistent cut rate during the life of the disc. 3M claims that fabricators can produce a completed surface finish in about half the time using Trizact, and that the product lasts 8 to 10 times longer than other types of abrasives. Trizact is used damp, with a light mist of water on the surface rather than a fully wet surface. A high gloss finish can be produced in five steps.
Investigate these new products. If you can reduce your sanding labor significantly, this is bound to have a significant positive impact on the profitability of your business.