It is usually the designer who decides on the production method at the beginning of the design process. So get ready for these five trends as vendors continue to improve their prototyping systems and materials.
Now that “rapid prototyping” is an accepted process, the next logical step is to emphasize the use of some of this equipment for manufacturing. No one agrees on the definitions of various prototyping and manufacturing terms –rapid, digital, direct, additive, e-, and so on. Regardless of the definition, the process of going from CAD drawing to end-use part continues to get faster. It is common to find 3D printers, FDM, SLS, SLA, polyjet, and metal casting equipment making end use parts for medical, dental, aerospace, and consumer product industries, among others. Continuing developments in metal and resin materials are making it easier to go to production.
Newer materials, like EOS NickelAlloy IN718 let you develop prototypes that can become production units.
Of course, when we say production, the question is — how many parts? The range is from 1 to several thousand. Noted Abe Reichental, CEO, 3D Systems Corp., “We see the industry moving more into the manufacturing arena. Over 40% of our activity is derived from direct and indirect manufacturing application of end use parts. This is a significant shift in the business model and in our focus and dedication in application now and in the future.”
Selective laser sintering (SLS) equipment produces aerospace parts used on the V-22 Osprey twin tilt-rotor airplane/helicopter, for example. These are production parts. The benefit is lower weight and dimensional consistency. Some parts for military aircraft are also made of SLS precision plastic material; again to save weight.
“Prototyping, while still important, has changed with the amount of direct manufacturing increasing,” continued Reichental. “The productivity and cost effectiveness in build envelope sizes, for example, has enabled a transition from traditional manufacturing methods to additive manufacturing methods without giving up any of the traditional benefits. In fact, additive manufacturing has added to the benefits by reducing labor, inventory, and inflexibility. We have enabled true mass customization and realized the dream of a flexible factory in a box.”
One trend in materials is combining different ones to create composites for both prototyping and final product.
“The use of prototyping equipment for manufacturing processes is speeding up,” agreed Frank Marangell, U.S. president and CEO of Objet, a company specializing in 3D printing. “You can print a mold and then inject resin to produce 100 parts in a day or two. But what do you call that, digital manufacturing or rapid prototyping, and does the term matter?”
Stratasys too has found that its customers are moving into the manufacturing arena. According to the company, 40% of its customers were using FDM for production several years ago. “We’re fairly confident that percentage has increased. Although most applications of our machines are still for prototypes, the growth rate of production applications is more than double that of prototyping,” said a company spokesman.
Noted Thomas Mattes, Vice President Technical Manage-ment P and Crossfunctions, EOS, “We see laser sintering being adopted more and more for the production of series parts. Nevertheless, in proportion to its potential, laser sintering is still considered too seldom for use as a manufacturing process.” Although it is very useful in the medical device industry, especially for disposable instruments in metal and plastic.
Materials are crucial, of course. The development of metals for rapid manufacturing applications continues; aluminum, cobalt, nickel, and titanium alloys are common. A big trend now is for vendors to develop prototyping materials that more closely match the end material, without the need to sacrifice properties or part performance. Noted Pedro Gonzolez, product manager, Roland DGA Corp., “Engineers can create prototypes in the same material as the final production component for actual real world testing. Instead of limiting testing to one material, engineers can open up their testing to a few more parameters to ensure that they have designed the correct component and selected the appropriate material.”
Objet also lets you more closely match your end material. You can develop composite materials from a choice of eleven physical materials. In addition, you can produce a complete part in one step, rather than build the components for later assembly.
Some vendors are looking to reverse the spread of “subtractive tools,” with the more “rapid cousins.” But subtractive is not shrinking yet.
CNC has never been viewed as quick, until recently. Continued Gonzolez, “In some applications, there is no perfect rapid prototyping solution, so subtractive rapid prototyping fills in when you need ultra smooth surfaces, tight tolerances, and a wide choice of materials.”
And, thanks to faster tool path programming, you can now obtain quality plastic or metal parts in a day or two. “I think the additive prototyping equipment was invented to circumvent the time and cost of toolpath planning for CNC machining,” said Brad Cleveland, president and CEO, Proto Labs. The company’s First Cut service uses software built from the ground up to remove all the time and analysis of tool path generation. “If, in the early days, industry had the ability to generate tool paths as quickly as First Cut does today, there may have been no need to develop all of these other types of prototyping systems.”
But it depends on the geometry of the part as to which one you pick. FDM suits parts with complex geometry. But if geometry can be injection molded or machined, then time and cost become factors.
“The biggest advantage of additive processes is that they can handle almost any geometry you can imagine,” continued Cleveland. “This is not true with molding. Plus, with additive, you don’t need tooling, which is another advantage over molding. The huge disadvantage, however, is part properties and finish. So using CNC machining to prototype instead of using an additive process now makes a lot of sense, especially if molding is eventually going to be used to support high volume production.”
A printer on every desk
HP has entered the 3D printer market through its arrangement with Stratasys. The two companies co-developed the Designjet 3D unit. Available in two models and starting below $13,000, this 3D printer creates accurate models in ivory colored ABS material, while the HP Designjet Color 3D printer produces single-color parts from a selection of eight colors. Several3D printer competitors see this development as a benefit to theindustry. “The differentiator amongthese products will be the quality of the part you get,” noted Marangell.
For all printers, the price per-formance ratio is getting better. As printers drop in price, yet maintain or improve in performance, you may see vendors offering the printers for rock bottom prices, knowing that they will have a bigger margin on printer materials.
Ready for service
Several vendors have broadened their scope and now offer direct manufacturing services. 3D Systems is gearing up to produce parts to meet those customer needs that exceed an in-house investment. Said Reichental, “We entered the parts service business in a big way late last year. We see this end of the business becoming more important. In some cases, the control required for direct metal manufacture may be better handled through a service provider.”
The shift from prototyping to end-use manufacturing continues to grow.
Others are offering unique products to aid you. EOS, for example, is offering Part Property Profiles (PPPs), which are profiles with reliable values for the dimensioning of laser-sintering designs. These values cover tensile strength, elongation at break, and moduli of elasticity for the horizontal X/Y-direction. The PPPs also have standard values for the orthogonal Z-direction for additive layer processes. Profiles for Balance, Performance and Top Quality are available for all EOSINT P and FORMIGA systems, TopSpeed and Speed for the EOSINT P760 and EOSINT P395. EOS will be making the entire characteristics of the Part Property Profiles available on M-Base, a public database established by the plastics industry.
Objet Geometries Ltd.