3D-Printed Stool Holds 220 Pounds

An Israeli company has produced a folding stool to demonstrate the capabilities of the 3D printing process. The demonstration shows that development of better materials is rapidly moving 3D printing into more of a mainstream tool for production of low volumes of complex assemblies. The stool can support more than 220 pounds.

Engineers at Objet Ltd., of Rehovot, Israel, produced the stool in a single print job using Objet ABS-like Digital Material (RGD5160-DM) -- a new, functionally advanced material that is jetted as a composite material on the Objet Connex multi-material 3D printer.

The folding stool, which is 19 inches tall, has similar high dimensional stability, thermal resistance, and toughness as ABS-grade engineering plastics, enabling it to repeatedly sustain the weight of a person, according to a press release from Objet.

"Our technology represents the most effective way of functionally testing complex design ideas. Whether skateboards or folding stools, the prototypes that come out of Objet Connex 3D printers look like the real thing and also perform like the real thing," Objet's executive vice president Gilad Gans said in the press release. "Not only can this stool carry the weight of a person, but it was actually printed in the fold-up position in a single print job and then opened-up upon removal from the printer to be used."

The demonstration is interesting because 3D printed objects are generally static pieces used as prototypes for evaluation early in the product development process. All of the major producers of 3D printing equipment are rapidly developing new materials that extend the capabilities of the process. One example is the Objet ABS-like Digital Material, "a high-impact material (65-80J/m or 1.22-1.50 ft lb/in), with high-temperature-resistance (65 degrees C or 149 degrees F and after thermal post treatment 90 degrees C or 194 degrees F)," according to the press release.

The material fits well for engineers who want to design products made of ABS-grade engineering plastics, including snap-fit parts, durable and movable parts, and products requiring drop-testing. The copolymer ABS (acrylonitrile butadiene styrene) is widely used because it is low-cost and has entry-level engineering properties.

Objet now has 65 3D printing materials, including 51 composite materials. Click here to see a video on Objet's new materials technologies.

In another dramatic example of the capabilities of 3D printing, a prototype car called the Urbee is the first car ever to have its entire body 3D printed by additive manufacturing processes. A model of the car -- produced in a development partnership between Stratasys of Eden Prairie, Minn., and Kor Ecologic, of Winnipeg, Manitoba -- was on display at Rapid 2011 in Minneapolis earlier this year.

According to a press release, "the electric / liquid-fuel hybrid reaches more than 200 mpg, highway and 100 mpg, city in U.S. gallons with either gasoline or ethanol (250 mpg highway /125 mpg city, Imperial gallons)." Stratasys pioneered the use of ABS and other production thermoplastics with its patented process called Fused Deposition Modeling (FDM).

3D printing is at one end of the additive manufacturing spectrum, while processes such as laser sintering and stereolithography (and also FDM) are at the other end, where the emphasis is on durable parts that can be used for implants or production parts for aircraft or equipment.

In an example of new materials for higher-end systems, DSM Somos has introduced Somos NeXt, "a next-generation material that facilitates the production of tough, complex parts with improved moisture resistance and greater thermal properties," according to the company's Website. It's a stereolithography material that comes close to replicating the properties of thermoplastic for functional testing and low-volume production.