Monday, November 5, 2012

Shop Thrives on Evolving CAM Capabilities



High speed, turn-mill and “hybrid” tool paths that combine functionality are among the Mastercam CAM software features that help keep this shop competitive.
 
 
 
 
Tony Johnson, co-owner of United Machine & Metal Fabrication (UMMF), says the success of his business depends on talented people and quality equipment. Unfortunately, good machinists and programmers are “scarce as hens’ teeth,” as he puts it, so it’s equally important to have CAM software that makes programming any part a customer might request as fast and easy as possible. At UMMF, Mastercam has filled that role for more than a decade of steady growth. Recent examples of software features that have made a difference at this Conover, North Carolina shop include high speed tool paths, “hybrid” tool paths that combine previously separate functionality, and tool paths designed specifically for multi-axis turn-mills.

 


Their equipment includes mills, lathes and horizontal boring machines from such builders as Mori Seiki, OKK, Okuma, Doosan and Mazak. To program these machines, the shop uses nine seats of Mastercam X6, including Lathe Level 1, Mill Level 3, Multiaxis and Solids. This version of the software is the latest in a series of releases that have provided UMMF with significant competitive advantages over the years, Mr. Johnson says.
For instance, the software’s high speed tool paths have improved cutting speed, minimized heat generated during machining and reduced tool wear, Mr. Johnson says. One notable example is peel mill, a high speed 2D tool path designed to peel away material layer by layer. According to the developer, it delivers efficient, constant climb milling via trochoidal-type motion with accelerated back-feed moves when the tool is disengaged.

Prior to the release of this toolpath, it took UMMF 27 minutes to machine 304 stainless parts that had already been plasma-cut to rough shape. In addition, heat generated during machining tended to cause the material to weld onto the cutter. Since applying peel mill, however, cycle time has dropped to 5 minutes, and inserts last 10 to 15 parts. Essentially, the company is cutting five parts with peel mill for less than the cost of cutting one part previously.

The shop has also benefitted from increasingly sophisticated tool paths that combine different strategies to reduce programming and cycle time. As an example, he cites an aluminum base mold for a carbon fiber chest protector. While simple-looking, this three-cavity mold once took hours to program because its straight sides and contoured floors required different types of tool paths. Recently, however, the use of hybrid tool paths that combine both types of operations cut programming time in half.
 

 
A relatively recent evolution at UMMF is the shop’s increasing reliance on its new Integrex E500H and E410H turn-mill machines from Mazak. Mastercam supports these machines, both of which can do the work of several mills and lathes, by enabling programmers to create sophisticated mill, multi-axis and lathe tool paths from within a single programming environment, Mr. Johnson says. Multi-operation strategies facilitated by the Integrexes and the Mastercam toolpaths that drive them have reduced lead times for complex parts by 50 percent or more in some cases, he reports.

He recalls one highly polished, 5-inch cylindrical extruder equipment part that once took a day and a half to produce. It required operations on three machines: a lathe, a VMC and finally, a rotary indexer to achieve a specific surface patter. Then, it required hours of polishing time to meet the 8-RMS surface finish specification. Recently, however, UMMF completed 12 of these components in less than a week. All roughing operations were conducted on the Integrex E410H using Mastercam’s high speed area clearance toolpaths, which use smooth motion to remove bulk material from the inside out. Then, fine rotary fourth-axis moves created a profile with sufficient finish quality to reduce buffing to a fraction of the time it used to take. The total productivity improvement amounted to nearly 200 percent!