Thermwood Begins Initial Testing Of New AM System

Back in July, Thermwood Corp., Dale, Ind., announced its new large scale additive manufacturing (LSAM) program. The company provided an update on the program and says that its development system performed well during initial additive testing through its entire operating range. Thermwood’s development system is supplied by a 1 ¾ inch American Kuhne extruder custom engineered for this application.

“It is my pleasure to support Thermwood beyond the design phase. This was a good opportunity to combine our polymer processing know-how with Thermwood’s CNC technology expertise to advise optimizations to melt piping and tooling design for this unique application,” said Kevin Slusarz, American Kuhne vice president of process technology.

 “Although it’s a demanding application, our extruder performed flawlessly during initial testing,” said Thermwood chairman & CEO Ken Susnjara. “We are quite pleased with our selection of American Kuhne as our development partner in this effort, not only for the quality of the equipment, but also for the service & support.”

Thermwood expects to fit this initial test machine, which can print parts up to 10-by-10 foot by five-foot-thick, with a five axis ‘subtractive’ gantry trim system, in the next few months. This will enable the system to perform both the ‘additive’ and ‘subtractive’ functions on the same machine. Called ‘near net shape’, this approach uses a high volume thermoplastic printer to quickly create a part that is nearly, but not exactly, the final net shape. The ‘subtractive’ function then machines the part to the exact final net shape.

Testing included initial validation of an all new MeltShape Technology for enhanced control of layer shape and improved bonding between layers, a new technique in the advancement of LSAM. This new patent-pending approach uses one or more shaping wheels to shape, form and compress the hot plastic melt as it is being extruded, insuring that each new layer is the proper shape and thickness and that it bonds firmly to previously applied material.

Thermwood plans to continue this development effort with the goal of offering these machines in a variety of large sizes for commercial applications, specifically targeting aerospace patterns and molds. Management cannot yet determine when the technology might be sufficiently refined for commercial rather than purely research and development applications. Thermwood plans to work with material vendors, R&D organizations and potential users in the ongoing development effort.