When it comes to a really “hits-the-nail-on-the-head” engineering program, it would be hard to top the IUPUI Mechanical Engineering Technology program at the School of Engineering and Technology. It is located at a shared campus, Indiana University—Purdue University Indianapolis (IUPUI).
Program Lecturer Ed Herger brings a strong manufacturing background in the field to his classroom. His career started with several years in industry, working in the R&D area of materials science, and moved on to the manufacture of products ranging from thermal instruments to exercise equipment. Then he began a career in education as adjunct professor in a Haas Automation Inc.-affiliated community college in California that stressed hands-on learning with Haas CNC machine tools and operations with software from CNC Software Inc., Tolland, Conn., developer of Mastercam CAD/CAM software.
“The students who elect to study mechanical engineering technology at IUPUI, as opposed to mechanical engineering, are exposed to more of what happens on the manufacturing floor, beyond design disciplines,” said Herger. “They are getting a lot of practical skills that they can apply right away after college, whether it’s Mastercam or Solidworks or some of the other software programs that we teach here.”
Students in the program spend the first two years covering a range of academic subjects before getting heavily into the technology itself beginning in their junior year. Until recently, the program used little online material and concentrated on a traditional curriculum of classroom lectures and practical projects. When it came to CAM software, Mastercam for Solidworks was taught as an add-in to the program.
“The direction we wanted to go in,” said Herger, “was to provide more CAM experience as well as online and external certificate opportunities. This meant concentrating on Mastercam and the online benefits of Mastercam University. This would give our students the option of receiving a proficiency certificate in addition to a Bachelor of Science degree, with online lessons both in our lab and on the students’ own laptops and home computers.”
Herger would take two or three units from Mastercam University and have students go through those units on their own and then give them an assignment based on the CAM operations or features shown in those materials. “In the class, I’ll put the Mastercam lesson, as well as my own assignments, on the computer and project them onto a large screen to share various operations with different work groups. In my class, students simply follow the online course from start to finish. I monitor them as they go through the lessons and I’ve been pleased with the way their certificate work has progressed. They have been pretty successful completing the Mastercam University assignments and my own assignments.”
Before students get to Ed Herger’s CAM classes, they first complete several courses in 3D modeling, as well as print reading and hands-on manufacturing processes. This is followed by a focus on parametric modeling using Solidworks. Once in Herger’s class, students begin receiving a strong diet of Mastercam. “I typically give them a big project to work on, such as mold work or dies for certain parts. My overall approach is to give them a more all-encompassing type of project as opposed to several small, specific exercises that offer little in the way of practical application,” Herger explains.
For example, Herger had them reverse-engineer a micrometer, a precision measuring device. Students designed several programs for tooling to make parts for the micrometer. They then figured out how to use advanced features of Mastercam to program the machine operations in the computer lab. “I try to give them a project with real-world application and I try not to give them too many hard guidelines on how to do it. They learn more effectively when they try to figure things out for themselves before I jump in,” Herger said.
Many of Mastercam’s features like Dynamic Milling make it possible to get the most out of CNC machines’ capabilities, according to Herger. “We’ve made a lot of big, complicated parts out of aluminum blocks, and a lot of what we focus on is 3D surface milling in order to make complex shapes for molds and dies. A good example of this is the U-shaped frame of the micrometer. It’s about a six-hour program and the die came out great. Of course, we do all the contouring and circle-type toolpaths required to complete the part using Mastercam from start to finish. I can’t really think of any three-axis CAM feature we haven’t at least touched on. The micrometer measured in the 0-1″ (0-25.4 mm) range and overall length of the device was about 3″ (76.2 mm) or so. We made a set of dies in tool steel to make the U-shaped frame and we made a small stamp, also in tool steel, in order to mark the sleeve of the micrometer with all the different numbers and markings.”
Also included in the micrometer project was a small mold for the rotating thimble. It contained tiny ascending numbers and position marks inside the mold. “They had to put a number of different fillets inside the CAD program and then make sure they could actually machine those tiny markings into the die,” said Herger. “The students took a few iterations to figure out which of the 3D milling surface approaches would be effective and certainly a few of them failed to generate toolpaths.” Herger reported that students learned that a parallel type surfacing toolpath was a little less sensitive to the “weird” geometries they needed to program.
The class also produced a marking die for all the 0.05″ (1.2 mm) marks on the micrometer sleeve, run as an inverse engraving program. “They machined out all the outside areas,” he said, “and left the raised marks using a 1/8″ (3.175 mm), 60o engraving tool. I try to impress on them that they should use every bit of this great technology that’s available to them to their advantage.”
Herger is especially enthusiastic when it comes to the big Indy car capstone project for his students. “Because we’re in Indianapolis,” he said, “it’s only natural that we’re in touch with the automotive racing scene and even have our own motor sports program.”
The Indianapolis Motor Speedway has a demonstration transmission from an Indy car on display at its museum. It’s cut away in a number of places so anyone can see what’s going on inside. Up until last fall it was a static display.
“We were fortunate to get the project from the museum where we would animate and automate the transmission so that it would be an interactive display that would rotate at a slow speed and allow visitors to shift it with a model of the steering wheel from the same car. All of the brackets that connected the small electric motor to turn the transmission, as well as many smaller components and a linear actuator to actually shift the linkage, were machined using Mastercam.”
Using the Dynamic Milling feature of Mastercam, students are able to push the machines pretty fast. “For example, when it came to the brackets,” Herger said, “we started off with a 2 x 2 x 2″ (50.8 x 50.8 x 50.8 mm) block of aluminum for a component that wound up as a 5/8″ (15.8-mm) thick plate with a couple of cylindrical bosses on the back that extended out somewhere between ½” and ¾” (12.7-19 mm) depending on location.” These bosses allowed the plate to be bolted up to the transmission while still giving it some standoff clearance.
“With the Dynamic Milling program, we used a ½” (12.7 mm) end mill and full depth of cut to get rid of most of the material. Essentially, we were removing all the material down to about 1¼” (31.75 mm) with the exception of the three cylindrical bosses,” he said. They then used a ½” (12.7-mm) ball end mill to leave a fillet at the bottom of the bosses. “We let Mastercam come up with the toolpaths and Dynamic Milling optimized cutting operations. The Verify simulation feature of Mastercam is something we use for every single program right before we run it.” By confirming all the steps of each program, they made sure there was no potential issue.
“I’d have to say, this capstone project, as well as many other projects, have been fantastic for our students and our program,” said Herger.
For more information from Mastercam-CNC Software Inc., go to www.mastercam.com or phone 860-875-5006.