Waterjet cutting is widely known for its ability to cut virtually any material to near net shape. These materials vary from rubber to plastics, composites to metals. Versatility is a benefit waterjet cutting brings to many businesses, including New Hampshire based company, Plan Tech. Plan Tech has been manufacturing urethane parts for over 30 years, providing products for diverse groups of industries. Urethane is a high-performance rubber that can be molded easily, shaped accurately, and offers many different finishing options. We’ve invited guest blogger Kevin Healy, Vice President of engineering at Plan Tech, to tell you more about how waterjet cutting has impacted their productivity. With their vast experience and in-house capabilities, they consistently deliver tight tolerance custom urethane parts.
Standoff height, the distance between the tip of the mixing tube and the material you are cutting, is important when cutting parts on a waterjet. In a previous blog I provided recommendations for proper standoff height. In general, stand off height should be about 0.100” (2.5 mm), or as thick as a dime. When your jet is perpendicular to your part, straight up and down, then raising the standoff will increase noise, mess and round the top edge of the part. You will lose a little cut power as well.
It’s important to maintain stand off under conventional waterjet cutting.
In 1984 the abrasive waterjet was released as a commercially available product. It was powerful, it was incredibly versatile; but it took a special operator to run it. Someone who was into it – who had caught the waterjet bug. Why? Because at the time, waterjet wasn’t all that easy to run.
I had the unique opportunity to be such a waterjet operator by getting into abrasive waterjet just one year after it was released. While in undergrad and grad school running the waterjet laboratory and demo center I could reference basic cut speed tables for what was believed (at that time) to be the best operating parameters. The table included water pressure, orifice size, mixing tube size, abrasive size, abrasive flow rate and the maximum cut speed for a dozen common materials at one or two thickness levels.
Taper left on a part was by far the biggest complaint from our customers across the world. As we have learned in prior posts, the faster you cut through a material with an abrasive waterjet, the greater the v-shaped taper. At the time, the only solution was to slow down your cut speed. The problem was, slowing down only minimized the taper – but rarely get rid of it; and slowing down costs shops a lot of money per part.