James Hendry, the father of gas-assisted injection molding, died May 24 at his home in Brooksville, Fla. He was 93.
Hendry's career spanned the entire modern plastics industry, beginning as a compression molding machine operator at Burroughs Adding Machine Co. in 1938. He remained active throughout his life, attending NPEs, speaking and even working on patents while in the hospital. In the last two years, he applied for four patents, said Steve Ham, a gas-assisted molding consultant and friend of Hendry.
A patent lawyer came to the hospital to write up his final patents, Ham said.
“Not many people had the endurance that he did,” Ham said. “He contributed at conferences at all times in his career. Hundreds and hundreds of papers. I think he had 104 patents.”
Many were for gas-assisted molding. The process works by pumping gas, usually nitrogen, into the mold. The gas pushes the melted plastic out against the mold, producing hollow parts.
Gas-assisted molding has grown rapidly in a wide range of parts, from large automotive components to small precision electronics.
Hendry entered the Plastics Hall of Fame in 2009. At that NPE — and every other one — he walked the show every single day, soaking in new technology. He finally relented at the last NPE, in 2012 in Orlando, Fla., and used a motorized wheelchair, Ham said.
“He told the story about being at NPE when JFK was shot,” said Ham, who nominated Hendry to the Plastics Hall of Fame. In recent years, the two formed a consulting partnership, H-2, and worked on Hendry's idea — began when he worked at Ex-Cell-O Corp. in the 1970s — to quickly heat and then cool the mold. In a Plastics News profile when he entered the hall, Hendry said he left Ex-Cello in 1981 when the company nixed the flash-heating idea, then for structural foam.
He kept thinking about thermal cycling for decades afterward. That illustrates Hendry's stick-to-itiveness to keep working on his inventions. “It was such a treat to be around him. He had such energy,” Ham said.
It was at Ex-Cell-O, in Athens, Tenn., that Hendry began to develop the basics of gas-assisted molding. The goal then was to eliminate the swirly pattern common on structural foam parts, and make parts with a smooth finish.
Born in Scotland as the youngest of 12 children, his family moved to West Virginia when he was a toddler. His father, a coal miner, died from cancer when Hendry was 8 years old. The whole family moved to Detroit when one of his sisters married a man from that city.
Right after high school, Hendry went to work at Burroughs, molding handles and cases for the company's adding machines. He became an apprentice mold designer. During World War II, he moved to Electric Autolite in Bay City, Mich., which was changed to war-time production of phenolic distributor caps for Army Jeeps, parts for the proximity fuse and torpedoes and other components.
“He fought World War II in the plastics lab,” Ham said.
