Partnership brings pellets to printers

Sept. 12, 2019
3D Platform and extrusion screw expert Tim Womer have designed extrusion systems that process pellets instead of filament for 3-D printers.

3D Platform and extrusion screw expert Tim Womer have teamed up to design extrusion systems that process pellets instead of filament for 3-D printers.

Womer was on hand at 3D Platform’s booth in May during Rapid + TCT in Detroit. There, 3D Platform showed how it has incorporated Womer’s TWW Micro Extruder into its WorkCenter 500 printer. The extruder has a screw with a helical compressed channel that generates pressurized heat for faster and more efficient compression, melting and mixing of the pellets, officials said. It can process pellets ranging in size from extra-small to standard-sized. The WorkCenter 500 has several temperature sensors that provide feedback to the control and data-logging system so that metrics are recorded.

“Instead of using filament, you’re going pellet-to-print. The plastic is not seeing an additional thermal history,” Womer said. “It is much more versatile.” The screw design is proprietary and Womer is waiting for the patent to be finalized.

The Micro Extruder can process materials from Techmer PM, Clinton, Tenn., including PP, HDPE, PC, very low-density PE, polylactic acid (PLA) and PLA/wood fiber.

Additive manufacturing systems that process pellets directly into parts are a relatively new technology, so material suppliers constantly are coming up with new material combinations, said 3D Platform President Jonathan Schroeder.

“For some customers and materials, this will require customization of the extruder, and Tim has a background in this exact area,” he said.

Schroeder said that several of the pellet extrusion printers that currently print less than 22 pounds per hour are not “true” pellet extrusion systems. This means they have an auger-style screw inside of a heated barrel. By contrast, Womer’s screw has various sections designed for mixing, metering and other functions.

Womer’s extrusion system is designed to use standard-sized pellets on larger extruders. For example, 3D Platform’s WorkCenter 500 machine has an extra-large build volume of 4.6 feet by 9.2 feet by 2.3 feet.

Additionally, 3D Platform soon will launch its WorkCell printer, which will have a print volume of more than 35.3 cubic feet. It will have a heated enclosure that will allow users to use polymers that typically can’t be printed at ambient temperatures, including engineering resins and high-performance plastics, according to the company.

Angie DeRosa, contributor


3D Platform,

Roscoe, Ill., 779-771-0000,

TWWomer and Associates LLC,

Edinburg, Pa., 724-355-3311,