Page 65 - MetalForming April 2013

Some hear about additive manu- facturing and immediately relate to its rapid-prototyping roots, says Shinbara, seeing the technology as just about creating models, but not as a means of production.
“Additive manufacturing came out of the rapid-prototyping world,” Shin- bara says, “so many people still apply the rapid-prototyping mindset to these newer technologies and processes. But that is just not the case. Some additive- manufacturing processes are too robust to be used only for rapid prototyping.”
At the other end of scale, some man- ufacturers envision 3D printing as a Star Trek replicator, where the press of a button instantly delivers a showroom- ready new car.
“People hear ‘additive’ and think it is a complete substitute for every single step and process required to produce a finished part,” says Shinbara. “It is not, and I don’t know if the technology will ever mature to that point. You have to ask if it is worth the investment to make finished parts—with all of the required tolerances, mechanical properties, den- sities and surface finishes—using only additive manufacturing in order to bypass all of the typical secondary processes. Doing that is costly, and I’m not sure it is necessary. Are you going to use additive to make 1 million alu- minum clips today? No, why would you? The business case isn’t there and you aren’t really exploiting the tech- nology as you could. Plenty of busi- ness cases exist where additive manu- facturing as employed today won’t make sense. We aren’t trying to pro- mote it as a cure-all. Additive manu- facturing is complementary.”
Compatible with Secondary Processing
As process and system control parameters advance over time, the technology may one day deliver parts directly to the shipping box. Researchers are finding that additive manufacturing produces parts that lend themselves to typical secondary operations.
“Traditional secondary processing applies to additively manufactured
parts,” Shinbara continues. “If you want to precipitation-harden such parts, for example, the same ASTM standards for other manufactured parts apply, and the secondary process yields positive results. Manufacturers should understand that traditional secondary operations that they already perform on their stamped parts can be performed on additive-manufactured metallic parts. With that understand- ing, additive manufacturing for part
production starts to make sense.” Beyond that, how can volume part production via additive manufactur- ing processes such as 3D printing make
sense? The answer relates to tooling. “You gain in affordability where you place multiple different parts in a single build—different and complex geometries without all of the tooling costs,” Shinbara says. “Then you can meet the required properties and net shapes by applying traditional
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MetalForming/April 2013 63
Tooling Technology
Industrial Examples
of Additive Manufacturing
Metalformers can take advantage of additive manufacturing in many ways, includ- ing prototyping, product development, part production and workholding assistance. We spoke with Stratasys, Eden Prairie, MN (www.stratasys.com), a developer and sup- plier of 3D printers and 3D production systems, to discuss how manufacturers are using the technology
in surprising yet
effective ways.
• Quality control:
A manufacturer has
saved hundreds of
dollars on each fix-
ture and hundreds
of thousands of dol-
lars annually in
reducing time-to-
market by transfer-
ring the manufac-
ture of CMM fix-
tures from tradition-
al machining to 3D
printing. Quicker,
more cost-effective
fixture production
cuts 61⁄2 days from
the traditional machining process and 29 days off of the prior 30-day cycle to com- plete first-article inspections.
• 5S: One company uses 3D printing to assist in its 5S efforts to create neat and orderly workspaces. Hundreds of brightly colored tool holders populate the shop floor, with designing and 3D printing the pieces taking only 2 to 24 hr. Company officials calculate savings related to time as well as to inhouse production and increased pro- ductivity resulting from effective 5S implementation. The same company also employs 3D printing to produce workholding components.
• Product development: An electric-motor manufacturer had previously contracted with a number of service bureaus to produce 3D models of component designs. Each model iteration required one to two weeks of lead time. An average of three iterations meant delays of as long as six weeks for a completed 3D model, and the company required hundreds of models per year. Now, with inhouse 3D printing model produc- tion has dropped from weeks to hours. Beyond cost reductions, the quick turnaround time increases flexibility in making design changes.
• Custom-part production: A custom motorcycle manufacturer had used injection molding and aluminum machining to produce one-off custom parts for its bikes. Doing so required three to four weeks of lead time owing to the need for tooling. Then, when the company was required to fabricate these parts within five days, 3D printing got the call. The process created the parts—all meeting accuracy and strength requirements— in the allotted timeframe at a quarter of the cost for alternate processes.
Shown are polycarbonate hydroforming tools produced from the patented Fused Deposition Modeling (FDM) additive-manufacturing process. The tools have proven lives of more than 600 cycles in forming aerospace-grade aluminum parts to 0.100 in. thick, according to Stratasys.