(Tile & Decorative Surfaces - April 1997)

Waterjet-cutting technology effectively meets the challenges posed by today’s design needs and goes beyond traditional cutting methods in providing quality materials in a cost-effective manner. But it’s hard to compete with methodology that is so flexible and effective.

By Jeanne A. Schmidlin - Richel, Inc

They want it all. Today, more than ever, consumers are demanding innovation and quality in the decorative surfaces they request. Clients are looking for unique designs that endure.

Waterjet cutting technology has risen to the challenge. It is proving itself as flexible, accurate and fast. And designers utilizing this technology are on the cutting edge.

Technology Everyone Can Understand

Waterjet technology is easily understood. The systems operate on the basic principle of erosion. Water, pressurized to 60,000 psi and focused in a narrow orifice, as small as .003", is directed at a material and cleanly passes through without shredding or crushing the material.

Low pressure tap water is subjected to a deionization process or reverse osmosis system. Simplified, this process removes solids, such as iron and calcium. The water then passes through a filtration system which removes particles down to .45 microns. Such purification is essential to maintain the pumps and high pressure seals. Without it, mineral deposits would develop, break off and eventually clog vital elements on the system.

The purified water enters an intensifier pump where it is pressurized up to 60,000 psi. After these three steps--deionization, filtration and intensification--the waterjet is ready to perform.

For products such as plastics and rubber, for example, water alone will penetrate the material. For harder materials, such as metals, glass and stone, an abrasive, usually garnet, is added to the cutting process.

In either case, the highly pressurized water or pressurized water and abrasive is passed through a narrow orifice in a cutting head positioned above the material to be cut. The size of the orifice is adjusted to suit the material density. Easily penetrated materials can be cut with only water using an orifice as small as .003", while harder materials may require the addition of an abrasive and an orifice up to .016".

The water leaving the orifice reaches speeds up to Mach 2.5 before striking the material to be cut. Materials lie on support grates held on tables which vary in size. Below the support grates, a pool of water steadfastly diffuses the force projected by the high pressurized nozzles. The water, once turned into a cutting tool, reverts to its placid state.

Methods of controlling the cutting path range from basic mechanically-controlled motions to sophisticated computer numerical control (CNC) motion systems. The multidirectional cutting capabilities and optional multiple cutting heads further increase the cutting capabilities and flexibility of waterjet technology.

The material which a waterjet system will penetrate are endless. To date, for example, some of the applications have been used with ceramic tile, marble and stone. The erosion process creates no burring or rough edges which often eliminates the necessity of additional finishing operations. There are no start holes created and parts can be optimally placed to fully utilize a piece of material.

Applications

The spectrum of applications for waterjet cutting ranges from the delicate to the stalwart. FDA regulations allow the use of waterjet technology in cutting food items.

Watetjets have proven themselves as both efficient and sanitary.

On the other extreme, abrasive waterjet systems (AWJ) are used to bombard armor plating in the assembly of M1 tanks and Bradley fighting vehicles. In between lies a wide spectrum of other applications. Artists, interior designers and shipbuilders are among the many who are embracing waterjet technology.

Waterjet technology is performing old tasks in a new and efficient manner. Complex and intricate designs and mosaics made of tile, stone and glass, often used in decorative surfaces and corporation logos, are now executed with the aid of a waterjet. Many of the projects would have been impossible to create without a waterjet because of the intricacy of the design and the fragile nature of the materials used.

Emblazoned Mosaic

In Spokane, WA, Precision H2O had its own challenge waiting.

A Chevrolet dealer, with letterhead in hand, wanted to recreate the Chevrolet logo in a ceramic tile mosaic. He wanted bright colors and distinctive edges, with a smooth polished effect. The finished product had to endure the high-traffic in his showroom and yet still be affordable.

Enter the waterjet. Its precision is becoming legendary. Unlike traditional tile cutting methods, the waterjet is unable to make an incorrect cut. This accuracy converts to savings in both time and material. But even more importantly, traditional cutting methods leave the edges of the ceramic tile with a raw cut edge. The raw cut edge seriously detracts from the smooth high-gloss effect desired.

Taking the small logo which appeared on the car dealer’s letterhead, a computer programmer scanned and digitized the image into the computer. In effect, the computer quickly replicated the picture in its memory. The designer immediately added the bold colors to the image and was able to glimpse the final product. The technology allowed the designer to play with the creation, altering colors and the size and placement of mosaic pieces. Once satisfied, the design was printed and ready for the approval of the Chevrolet dealer.

Once approved, Precision H2O looked to its parent company, Quarry Tile, to manufacture the tiles specifically for this project. It is this partnership between Precision H2O and Quarry Tile that allows Precision H2O unlimited options in selecting the optimal colors and types of tile for a particular project.

With the design complete and the materials available, it was time to employ the power of nature--erosion--20th century-style.

The uncut tiles were placed on the waterjet cutting table and bombarded with a mixture of high pressurized water and garnet. Each piece of the mosaic emerged precisely cut and was then refired to create healed edges. This refiring technique successfully eliminated the raw, unfinished edges that result from the use of traditional cutting methods. This refiring process is critical in order to achieve a professional look in the final mosaic. What little fray or raw edges remained dissipated as the tile piece was refired and glazed. It is the final touch, the refiring of the individual pieces that makes Precision H2O’s creations truly unique and beautiful.

Each grid, or section, of the final floor design was reassembled, labeled and packaged. A computer-generated key provided the map to the puzzle. The medallion was then shipped to the Chevrolet dealer and installed in the same manner as standard tile. The focal point of his showroom, a beautiful mosaic, as crisp and smooth as the highly lacquered autos that surround it.

There’s no question but that waterjet cutting technology effectively meets the challenges posed by today’s design needs. It is hard to compete with a methodology that is so flexible and effective.