From Model to Toolpath, Direct

End User: Bargas Medical Manufacturing, Inc., Flatonia , Texas

Industry: Orthopedic instrument and implant manufacturing

Challenge: Quickly and accurately create milling and turning toolpaths to machine low-volume, short-leadtime components

Solution: CAM software that generates toolpaths directly from customer electronic model files. 

Bargas Medical Manufacturing Inc., Flatonia , Texas , performs quick-response, low volume machining of R&D and custom orthopedic implants and surgical instruments. "If I build thirty or forty of something that's a lot of volume," said Felix Bargas, president, noting that his customers "need someone who will give them good turns." Typically, Bargas machines a steel or plastic prototype that is tested by a surgeon who provides feedback. "Then I'll build 3 or 4 or half a dozen more. Sometimes they come back to me to build additional quantities." In addition to fast turnover, quality is paramount in Bargas' business. To meet the requirements of orthopedic OEMs and expand its customer base, Bargas is releasing its Quality System manual that details its compliance with ISO9001:2000 standards.

As a way to speed the process and maintain quality, Bargas creates toolpaths directly from customers' electronic design files: "They'll send me a model. I'll drive all my toolpaths right off it," he said. Bargas uses the 3-D SolidSurfacer module of Virtual Gibbs CAM software (Gibbs and Associates, Moorpark , Cal. ) to read solid models produced in various CAD systems. "I prefer Parasolid files, but I can take others too," he said. Recently a customer was concerned there would be difficulty importing a complex file, "but it just came right into Gibbs and literally within minutes, I was creating toolpaths." Bargas said. Jason Heyse, president of Texas Offline Inc. (Houston, Texas ) a GibbsCAM reseller, said "bringing in solid models from customers makes life so much easier. The alternative is working off a blueprint and trying to figure out what the engineer wants." Bargas previously worked from models for 3-D machining alone, but now requests them for 2-D machining as well. "It just really helps to clean things up and process product a whole lot faster," he said.

Athough he generates toolpaths without blueprints, Bargas often creates what he calls "in-process drawings" to minimize confusion for his machinists. "Complex 3-D drawings can get very busy," he said. The Gibbs software enables him to note dimensions for specific geometries and operations and print out a drawing.  "It may sound time consuming, but in the long run, it helps us flow product a little quicker," he said.

Creating a toolpath is only half of the process, Bargas said, "The other half is running it through your post or translator to put it into a language that your machine will understand."  Bargas has two Hitachi Seiki VS-50 CNC vertical machining centers and a Daewoo Lynx 200LC CNC turning centers. "I used to do a lot of proofing of code. Some of these programs involve a lot of 3-D ballnosing and run 45 minutes or an hour. To sit there and dry run a program like that and watch it like a hawk is very time consuming."  With the Gibbs software, Bargas said, "the post comes out so clean I don't dry run anything any more. I just send the code to the machine, load my tools, preset them and away I go. That's my confidence in Gibbs."    

Bargas also appreciates Gibb's software's ease of use. Although he began as a machinist twenty years ago, he worked in supervision for seven years before starting his own business in 1999. "I got away from machining. When we started our company, all of a sudden I had to get right back into machining and programming. Gibbs made it so easy, it thinks like a machinist thinks," he said. Jason Heyse  said "the learning curve for the software is very short. He can try different types of toolpaths to see which one looks the best and cuts the best, then can check it with 3-D simulation on the computer before even getting it out on the machine tool." 

This article was originally published in the May 2003 issue of Cutting Tool Engineering as the cover feature article and is posted here with permission. Copyright (c)2003"