Hohl, John
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John Hohl
Newark Die Company
Inducted 1987
John Hohl (1883 – 1947) pioneered developing injection molds and injection molding techniques for the plastics industry. Hohl was the acknowledged “master” of the precise and intricate specialty of die hobbing, which enabled the production of duplicate, uniform mold cavities from a single master for multi-cavity injection molds. The hobbling process dramatically accelerated the ability to produce high-quality, tight-tolerant, multi-cavity molds.
In 1918, John Hohl formed the Newark Die Company. He established many basic mold-making concepts that are still in practice today. Hohl contributed to improving plastic injection molding methods through unique, patented mold devices and techniques that greatly accelerated the growth of the injection molding industry. He also created designs to construct test molds for research institutions and universities.
In 1936, he constructed a special laboratory injection molding press for Charles F. Burroughs with a complete set of experimental molds to establish such basic data as molding pressures, temperatures, counteracting forces, and flow speeds of different materials under varying molding conditions. These data contributed to advancements in injection molding machines and mold design. These efforts are considered some of the first “scientific” experiments brought into the molding field that had started as an “art.”
Areas of Expertise:
Plastics machinery, Plastics management