Cleveland — Two students from the Pennsylvania College of Technology presented research into 3-D printed inserts for rotomolding at the Society of Plastics Engineers' Rotational Molding Conference.
The students, Logan Tate and Anthony Wagner, printed inserts at the plastics laboratory of Penn College in Williamsport, Pa. They used ABS material donated by Stratasys, and Rotaloc steel inserts.
Paladin Sales of Uniontown, Ohio, donated an EZ Logger, for measuring in-mold temperature throughout the rotomolding cycle.
The students printed ABS rings to represent the inserts. They inserted the rings into a mold cavity and rotomolded test parts from polyethylene and polypropylene. They tested the level of adherence of the rings to the molded plastic part.
Tate said the disadvantages of the rings included thermal degradation and heat distortion.
Wagner said they tried using some Gorilla Glue to get the rings to stick. “That got us onto thinking that maybe we've got to surface-treat the insert,” he said.
Wagner said they never expected 3-D printed inserts to replace steel inserts, but wanted to study the process to turn out quick inserts for prototyping.
Logan said the researchers want to go back to the lab to run more tests, such as torque testing and thread pulling. They also want to keep working on surface treatments, plus look at lower processing temperatures and longer cycle times, he said.
