Is the Juice Worth the Squeeze?

Is the end result of metal AM worth the effort it requires? Students of UL AMCC learn to ask this question at every stage in the process.
#metal #basics


Facebook Share Icon LinkedIn Share Icon Twitter Share Icon Share by EMail icon Print Icon

Although UL is known as an authority on safety, its Advanced Training on Metal Part Production course is more than just safety training. The class, offered at the UL Additive Manufacturing Competency Center (UL AMCCC), covers the entire 3D printing ecosystem within a company. Each student leaves with an understanding of all the necessary steps to make a metal part. In addition to learning how to run, load and unload the machine, students also learn how to receive, test and manage the material; maintain the machine and periphery equipment such as wet separators; and manage waste.

“When working with 3D printing, end users should always be evaluating whether the end result is worth the effort required to obtain it," says Jon Walker, CMTSE, an area sales manager for EOS of North America who has taken the class. An expression commonly used during UL training encompasses this valuable lesson: “Is the juice worth the squeeze?”

"This thought process applies to everything from part design to support structure allocation to postprocessing,” says Walker. Here’s how that process plays out in some of the key stages in additive manufacturing. 

Metal AM parts have a greater amount of postprocessing compared to plastic AM parts, and that needs to be considered from the very beginning in their design. “The challenge here is that if you don’t think about the downstream processes when you are setting up the build or designing the CAD, you are setting up the entire manufacturing chain for failure,” says Ed Tackett, director of educational programs at the UL AMCC.

The course reviews what actually has to happen to link metal AM to the CNC shop, and how the parts benefit. Working with the machine shop and postprocessing team to develop a design can result in a part that needs less cleanup or is easier to set up in a milling machine, for example. Also, consider what will be necessary to machine the part after it is printed, such as soft jaws, and how to provide them to the postprocessing team.

Walker says that one of the most intimidating aspects of DMLS is support structure setup. “The UL training helped me understand the logic built into the Magics software for auto-generation of support structures and how important it is to think about postprocessing requirements when setting up the support structures," he says. “This permits a setup with minimal build time and efficient postprocessing requirements.”

The course also helps students develop their design allowables package on AM systems. “Each material for every machine builds a little differently, so students are shown how to figure it out on their own machine(s)," Tackett says. "We provide CAD files, instructions to build them and how to evaluate the results to ensure design engineers know what they can and cannot build at their facility on their equipment. This way, they can channel that information back upstream to the engineers to avoid designing parts that the machine can’t build." 

Expectations are also discussed. Metal AM's roots are in metalworking, so metalworking, CNC machining, turning and polishing must be understood before attempting to institutionalize AM within a company. However, CNC machining can often be set up and run the next day to make production parts, and that is not the case with AM.

“Many people walk a show like IMTS, see a metal AM machine and think ‘We make metal parts. We should buy one of these.' They buy one and then drop it on the engineer with the same expectations of a CNC machine,” says Paul Bates, general manager of UL AMCC services. By better understanding the full process up front, companies can make better decisions about whether the "squeeze" is worth it.