Injection Molding with an Additive Manufactured Tool

Steinwall is always researching and discovering how to help improve the market and saving our customers money. Our team has recently spent much time and research into an intense study performed along with article written that was recently published in an issue of Polymer Engineering and Science journal, one of the most highly regarded journals in the field, serving as a forum for authors of treatises on the cutting edge of polymer science and technology.

The overall idea on the study was to cover the 3 main topics:

1. Addressing our customer’s concerns for injection molding tool costs
2. Awareness of 3D prints (e.g. additive manufacturing)
3. Research solutions and developing a more affordable tooling option using 3D printing

This research led to a collaborative effort between Steinwall’s engineering team, customers and vendors to study and understand the benefits of this solution, culminated with industry recognition and a journal publication.

In depth, this study examines the viability of using additively manufactured injection molding tools for short run proof‐of‐concept plastic parts by assessing the quantity and quality of molded parts. Prototyping injection molded parts traditionally can be very expensive, but with improved additive manufacturing materials and techniques such costs could be reduced. To prove this, plastic tools were made by using PolyJet and Fused Deposition Modeling out of Digital ABS, FullCure 720, and ULTEM 1010 materials in this study. The test tools were then compared to the standard P20 metal tool by molding acetal, polycarbonate (PC), and polypropylene (PP) in each tool type. The molded parts were analyzed for processing effects on part shrink, physical, and mechanical properties. Testing concluded that parts molded with additively manufactured tools performed comparably to parts made on a P20 tool. However, the quantity of satisfactory parts molded in acetal and PC were consistent with the literature at 10–100 parts. Conversely, molding in PP suggested that processing with additive manufactured tools could exceed 250 parts.

Study done and authored by: Patrick Simpson Autumn D. Zakula Jake Nelson Jeremy K. Dworshak Eric M. Johnson Chad A. Ulven

https://onlinelibrary.wiley.com/doi/10.1002/pen.25192
POLYM. ENG. SCI., 59:1911–1918, 2019. © 2019 Society of Plastics Engineers