Do you think 3-D printing capabilities will evolve to the point where they're good enough for low-volume production of parts for end use?
Probably not for a long time. In order to become a viable low-volume plastic production method, 3-D printing would have to overcome several major obstacles. The first is the narrow range of materials the technology can use. The thousands of individual and blended resins in use today evolved for a reason, and any process that doesn’t support most of them will have limited use in producing finished parts.
Second, additive processes like 3-D printing build parts in layers, each acting as a foundation for the next. As a result, the long chain molecules that give plastics their strength are laid down within, but not between, layers. This weak bonding between layers can lead to delamination and breakage under stress, a fact verified in side-by-side testing of layered and molded parts.
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In injection molded parts, the only place such weakness can occur is at knit lines, which are avoided wherever possible.Layered parts, on the other hand, have weak interfaces at every layer, producing parts that are only suitable for unstressed applications.
Not only does the layering process produce weaker parts, it also leaves a rough surface finish not representative of the cosmetics associated with an injection molded part.
The final obstacle to 3-D printing for low-volume production is its cost compared to that of rapid injection molding. Because 3-D printing is relatively slow and equipment-intensive, the per-part cost stays relatively flat as quantity increases. Rapid injection molding, on the other hand, can produce parts quickly and at a cost that drops sharply as production volume increases.
In short, to be suitable for low-volume production, 3-D printing would have to greatly expand its range of usable resins, increase its interlayer bond-strength, produce smoother finishes and significantly reduce cost per part, all of which would require fundamental change in existing technology. In the meantime, however, it remains an excellent technology for producing concept models quickly and cost-effectively.
 Bruce Bradshaw
Objet Geometries
Director of U.S. Marketing
www.objet.com |
As a matter of fact, it is already happening. Companies like Ivivi Technologies, which develop products in the medical device market, have found that Objet’s 3-D printers can not only produce more prototypes, but are also cost-effective for short runs of final products.
However, not all rapid prototyping systems are suited for products that are ready for the end user. This capability is directly dependent on the system’s ability to output parts that function in a real world environment and enable:
- Agility – Given the importance of an organization’s ability to be fast-to-market and agile as market conditions change, 3-D printing systems must output products that exactly reflect the design team’s concept and intent, while delivering a quality part in an expedited way.
- Durability – Outside vendors have long offered firms so-called expedited product manufacturing, only to deliver extremely fragile items that can shatter easily. Only 3-D printed products using the latest in high-quality materials will stand up to requirements in a given market, fulfilling their final purpose.
- Smooth Surfaces & Fine Detail – Today’s consumers have grown accustomed to devices that maintain a high-level of quality. Therefore, they are unlikely to embrace a short-run manufactured product that does not meet the same level of quality they have come to expect. Products that are coarse and/or cumbersome in any way will not be acceptable. With today’s 3-D printer technology, these consumer-driven quality factors don’t have to be sacrificed in a short-run production process.
In short, 3-D printing technology has advanced to the point where the possibilities for quick and cost-effective production can be met for both prototypes or finished products.
Since the inception of the “3-D printer” in the mid-90’s by BPM, we have all wondered how long it would take to do two things: the first was to eliminate the need for traditional rapid prototyping equipment by having 3-D printers in every office; and secondly, to evolve the traditional rapid prototyping system to become a low-volume manufacturing solution. Neither of these “future developments” has transpired after 15 years, but they are both moving toward these ideals.
It is important to understand there is a difference today between the 3-D printer and the rapid prototyping system. They are both part of the additive fabrication type of manufacturing, which means the parts are made by building consecutive, very thin layers of the parts.
I believe rapid prototyping systems will definitely become viable systems that provide-low volume production parts. Actually, this has been occurring for years and becoming more prevalent. We call this Low Volume Layered Manufacturing (LVLM), also known as Direct Digital Manufacturing (DDM). It has some significant advantages, including the ability to have “tool-less” parts which allow you to change designs at anytime; design parts for the product instead of designing them for manufacturing (DFM); and the ability to consolidate many parts together, which can reduce the number of unique parts in a product.
3-D printing systems will continue to expand to the point that all design firms will have their own systems allowing them to make more “prototypes” than they do now. This will increase the quality of the product and reduce the time it takes to get it to market. Currently, it is possible to buy a reasonable quality system from $20,000 on up.
With increased competition, the consumer will soon be able to buy high quality “prototyping” printers for less than $20,000. This is analogous to consumer printers. At one time, we used to buy low quality dot matrix printers, but now we buy high quality color laser printers for the same price. As the technologies expand and the prices of systems decrease, we will be able to experience a whole new way to develop new products and launch the world into mass customization.
Yes. It’s already happening. With an “on demand” global network of more than 100 3-D printing systems, RedEye has a lot of insight into customer applications and is seeing customers utilize its 3-D printing capabilities beyond rapid prototyping to “on demand” Direct Digital Manufacturing (DDM). RedEye delivers the entire DDM experience, starting with an idea and ending with a marketable product, resulting in competitive advantages and operational efficiencies. We are positioned to be the “Factory of the Future” for our customers.
As an example, Ablation Frontiers initially engaged RedEye as a bridge to tooling, but later used DDM to produce the final product. Ablation Frontiers — a medical device company that develops novel technologies to restore normal heart function in individuals with cardiac arrhythmias — needed to produce 2,500 ablation tools to meet a trade show deadline in four months. It asked RedEye to produce 500 rapid prototype products while its tooling operation caught up with production.
It chose RedEye polycarbonate (PC) ISO Class VI materials, which can be sterilized for clean room environments and medical devices.
As prototyping began, however, Ablation Frontiers began making small product improvements, each stretching the cost and timeline if the original tooling plan were to continue. After seven iterations of its product, Ablation asked RedEye to create all 2,500 products in order to meet its four-month deadline and stay within its budget.
The “Factory of the Future” is here today. If it can meet the demands of a medical device company, it is ready for anything.
During the past few years, 3-D printing capabilities have improved greatly. Modern machines provide much greater accuracy and speed. At Helix Design, we’re impressed with the production-level accuracy we get from an Objet 350v printer we use in-house.
Materials are improving and evolving, but still do not match production-engineering plastics. Although some companies today are making production parts from 3-D printers, it is not a mainstream solution for most markets. Material choices, colors and surface finishes are limited and inferior to production choices available.
In the short term, and as materials become more sophisticated, I see 3-D printing being used extensively for mold masters and molds themselves. This may become a more economical tooling alternative to traditional machining – and a significant cost benefit for low-volume production. Longer term, 3-D printed parts may become a practical choice for non-cosmetic, low-volume production as the materials become better suited for production applications, and as printer speeds increase.
For cosmetic parts, the current inability to add textures and custom colors will limit production-level appeal, at least with the present generation of 3-D printers.
There are already additive fabrication machines on the market that can produce, in low-volume, components for end use. Companies have advanced to the point where their machines are used for Direct Digital Manufacturing (DDM) in one of two different applications.
The first is to directly manufacture components that are installed in a product, which is sold. The other application is to build a fabrication and assembly tool, such as a jig or fixture, which is used in the production of an end product. The fabrication and assembly tool application is more widely used today than making components to be installed in an end-product.
End-use components built via DDM are more typically interior rather than exterior components. This is because although they can be “finished” to resemble typical end products, directly from the system they don’t look as smooth or familiar as a component produced through a traditional method, such as injection molding.
DDM is not for mass-production, but can be very cost-effective on custom products and short production runs of up to approximately 2,000 units.