Flexibility and adaptability are qualities we look for in working relationships. It is also true that we seek the same attributes in the tools we use. Routine purchases are one thing, but acquiring capital equipment exaggerates the requirement to balance needs, wants, and ROI (return on investment). Will the investment offer a capability that we don’t currently have? Will it speed development time, and by extension, save money for our clients? Can it be used on a daily basis? The OMAX JetMachining Center embodies all of those qualities.
Jeff Smith, M.E., P.E., is one of our in-house OMAX experts.
The abrasive machining process.
The cutting (a high-pressure abrading operation) process goes like this. First, the material to be cut is clamped into the bed of the machine (which weights 5200 pounds – it’s big). The cutting path can either be programmed with the on board computer, or imported as a .dxf or .dwg file. The operator inputs the type of material to be machined, chooses the quality of cut desired, checks the tool path, and presses the big red button. The water level in the bed rises covering the work piece (cutting is done under water), and work begins. A 40 HP electric motor powers water at 55,000 psi through a small sapphire orifice, which is then mixed with a fine garnet abrasive. This powerful jet of abrasive-laced water exits the cigar-sized nozzle at the speed of sound and cuts right through whatever material it contacts, even two-inch titanium!
The OMAX logo resting in a bed of abrasive garnet was cut from 1/4" aluminum. Note the fine surface finish, and the thin-wall cells.
Fast and Accurate
The OMAX is fast, and can accurately machine material less than one inch thick (above that thickness, it’s harder to hold tight tolerances) into almost any two-dimensional shape imaginable. The edges look smooth and satin-like, similar to a sandblasted surface. Post finishing of the burr-free edges are usually not required and tolerances can be held within ± 0.005” or better.
Benefits for our clients
In this case, we successfully executed the balancing act. Operational costs for the new machine are relatively low. That, the ease of set up, and the ability to cut just about anything, are key qualities that make the OMAX especially useful for prototyping and short runs. Best of all, many parts that could take hours to program and mill with traditional CNC methods can be completed with the abrasivejet in a matter of minutes.
Jeff "machined" this lucky granite dragon
in less than six minutes.