A recently introduced elastomeric 3D printing plastic with very good hardness characteristics is creating a lot of excitement among design engineers, who have struggled to find additive manufacturing elastomers that have properties approximating actual molded elastomers.
UL Prospectors says that the material—called NinjaFlex—is one of the most searched 3D printing materials in its plastics resins database.
Fenner Drives of Manheim, Pennsylvania, introduced NinjaFlex last year.
“Until recently, prototyping flexible components was a time-consuming and cumbersome process,” says Stephen Heston, product development engineer for Fenner Drives. “It was a big gap in the market, because so many engineered products utilize elastomeric parts. Without materials that closely approximate the properties of the end product, it is impossible to create truly functional prototypes.”
An engineering team at Fenner Drives began experimenting with polyurethanes for a link-belt project at the company to find an acceptable prototyping material. In October 2013, Fenner Drives did a soft launch with NinjaFlex TPE printer filament, initially available in four colors: Snow, Fire, Midnight and Sapphire. Now there are nine colors, including two metallics.
“We fill a market space that is not currently occupied by any other filament manufacturer,” says Stan Kulikowski, applications engineer for Fenner Drives. “Most filaments currently in the market are in the 45D-75D (Shore D) hardness range; we are playing in the 85A (Shore A) range — think hard polycarbonate sheets versus flexible shoe soles, respectively.”
A recently announced addition to the product line, called Semi Flex, offers a Shore Hardness of 98A, improved print speed and shock absorption with some sacrifice in flexibility.
NinjaFlex can be used in many of today’s popular 3D desktop printers, including MakerBot, MendelMax, RepRap, Ordbot, Airwolf and Lulzbot models as well as most industrial 3D printers.
NinjaFlex has also been used in medical prototyping. According to a television news report in Kentucky, doctors used NinjaFlex 3D filament to print a model of a child’s heart at a cost of $600. The model was used to prepare for a surgical procedure.
Fenner Drives is a division of Fenner PLC and has ISO 9001 certified production facilities in Manheim and Wilmington, North Carolina. The company focuses on products for power transmission, motion transfer and conveying applications.
“It may seem like an unusual move for a 103-year-old belting company in Lancaster County to create a 3D printer filament, but the core materials and technology are similar,” says Jack Krecek, president of Fenner Drives.