Abrasive machining centers are now being used to cut 10" thick stainless steel, as well as 0.020" thick plastic sheeting, all in the same day. The range of applications and the benefits of no heat-affected cutting zones, while achieving +/-0.003" tolerances in abrasive cutting of alloys, have prompted many people to ask if waterjet cutting is for them. Making the proper decision depends on honest answers to some serious questions.

First, does waterjet machining have a place in the shop; specifically, what would it be used for, and what existing operations would be changed over to waterjet machining? How much would be saved by using waterjet? Would the system address long-and short-term goals? Would special training in maintenance be required, and how could training circumvent the normal learning curve?

What software is needed, and could the system be retrofitted to an existing CNC(computer numerical control) gantry; or is a PC (personal computer)-based control more appropriate? Are the parts to be cut highly corrosive, or must they be cut without getting wet? Can the water be recycled? Are special power supplies required? Finally, when it comes to system operation, are there service centers specializing in machining contract services or would it pay to invest in an in-house system?

In 1992, Richel Inc., a consulting group in Tallmadge, OH, started evaluating the special needs of waterjet applications. Richel’s President, Richard Ward, says, "It became apparent a full-service consulting group covering all aspects of precision waterjet machining was needed: from the development of complete business plans for new and existing operators, through the selection and implementation of equipment; including market evaluation, telemarketing, fax and mail service, costing controls and systems, CAD/CAM (computer-aided design/computer-assisted manufacturing), and assistance on challenging projects."

Initially, services were primarily used by existing operators looking to train their staff on cutting techniques to improve production rates. However, with the growth in the industry, about 50% of all new business originates from organizations investigating waterjet machining for their own use or to supplement existing job shop operations.

When purchasing equipment, the OEM (outside equipment manufacturer) will typically offer training in machine operation and maintenance. Some manufacturers offer full training on-site, including working with the new user in stripping down and rebuilding pumps prior to leaving. All manufacturers offer hands-on training at their facilities, with each class lasting three to four days. Some level of training is necessary to ensure that the equipment is operated and maintained properly.

During the evaluation of a prospective waterjet operation, every effort is made to determine all costs and ensure that no surprise expenses occur. In evaluating existing facilities, an in-depth analysis addresses power requirements, the water supply, drainage, computer capabilities, clean rooms and other miscellaneous equipment. Every aspect of the installation is examined, including the location of the pump, selection of the CNC equipment, and the logistics and handling of materials and finished product.

Determining the viability of the application means analyzing the parts to be cut, production requirements, cost of existing parts and the allowable downtime. Market research is often an integral part of the analysis, identifying the advantages of waterjet machining vs. more conventional methods. In many cases, waterjet machining will free up much-needed time on existing equipment; for example, CNC milling machines primarily used for roughing operations. The waterjet can cut the part to near-net shape, accelerating the entire process.