Robert Barr said the 1960s was an exciting decade in America. He's talking about rapid-fire innovations in plastics resin, machinery and screw design, not bell-bottoms and the Beatles.
Guys like me that cut our teeth in the sixties were really on the upswing of the plastics industry. Things were going crazy at that time, Barr said. Major advances in screw technology, extrusion and large-part blow molding have earned Barr a spot in the Plastics Hall of Fame.
He was nominated by two blow molding experts that are already in the hall Don Peters, a 2000 inductee, and Samuel Belcher, part of the class of 2003.
Belcher cited Barr's uncanny knowledge of plastics machinery. Barr said that like many screw designers, he benefited from working with plastics machinery to understand what the screw needs to do. Most of the people that are involved in screw design worked for extruder manufacturers, he said.
In the mid-1960s, Barr got the U.S. patent for the first commercially available barrier screw, dubbed the Barr screw.
Barr, 79, was born in Columbus, Ohio. He graduated from high school in New Jersey, and then earned a degree in mechanical engineering in 1954 from Rensselaer Polytechnic Institute in Troy, N.Y.
His first job had nothing to do with plastics. He worked for a year testing jet engines at the Allison Division of General Motors Corp.
The only thing that was memorable about that was the Indianapolis Motor Speedway was right across the street, so we got free tickets, he said.
His second position was equally exotic.
He worked at the U.S. Army Chemical Corp. in Maryland, where he developed high-altitude temperature sensing to detect the release of bio- chemical warfare materials.
In 1958, Barr became a development engineer at John Waldron Corp. in Highland Park, N.J. For two years, he worked on equipment for paper coating and other web-type machinery. He designed an air-sensing guide for blowing inserts into magazines.
There's a reason Barr fondly recalls the sixties. His plastics began in 1960, when he became research and development manager of the Waldron Hartig machinery business. John Waldron had been bought by Midland Ross Corp., a diversified manufacturer that owned Hartig extruders. Barr was responsible for expanding Hartig into blow molding machines, both accumulator-head machines for making big industrial parts and reciprocating- screw machines for packaging.
He developed several new screw designs, including a pin-type screw that improved melt flow in the metering section.
Barr's screw development took off when he got promoted to Waldron Hartig's director of research and development. That's when we were running tests for customers on all types of products, so it's just natural that we would work on screw designs. Just being exposed to those kinds of problems, we actually developed an ability for screw design, he said.
Waldron Hartig moved into a modern new factory in South Plainfield, N.J. Barr became sales manager of the blow molding and extrusion machines. He hit the technical-paper circuit, giving more than 200 presentations at meetings of the Society of Plastics Engineers.
The Barr screw was the first commercially available barrier-type screw, he said. According to Barr, Uniroyal Inc. had a rubber barrier screw and Swiss extruder maker Maillefer SA had developed barrier screws, but used them internally.
Barrier screws ensure that only melted plastic exits the extruder. One of the problems with extrusion in those days was it was hard to get everything completely melted, Barr said. The barrier actually separates the unmelted solids from the melted material. The barrier prevents the solids from getting out. They have to melt to get out.
Today, barrier screws are commonly used in extrusion and injection molding. The patent expired on the Barr screw in 1986.
Barr struck out on his own in 1972, forming Barr Polymer Systems Inc., together with a group of former Hartig employees, to make blow molding machinery. The company was based in South Plainfield, the same town as Hartig.
You know, you get to the point where you say, 'Hey. I can do that!' Barr said.
The chief engineer, John Hsu, developed an accumulator-head blow molder and got a patent for the Maxmelt barrier screw.
We wanted to make the machine simpler to maintain and we also wanted to incorporate our own ideas in the screw design, Barr said.
The company sold 22 machines, to mold everything from 55-gallon drums, gas tanks, and the classic plastic tricycle of the 1970s, the Big Wheel.
But after just two years, financial struggles hit, and the owners decided to sell Barr Polymer Systems to the Uniloy Division of Hoover Ball and Bearing Co. Uniloy was a leading maker of reciprocating-screw machines for molding plastic milk jugs.
We were an engineering and marketing success, but a financial failure, he said. We had good customers and good designs. I still get calls from people asking for parts.
Barr went along with the new owner, becoming technical director and integrating the accumulator-head machines into the Uniloy product line. (Cincinnati Milacron Inc. later bought Uniloy.)
In 1976, Barr, together with Chan Chung, founded Robert Barr Inc., a screw company. Barr had hired Chung back at Hartig in the early 1960s when Chung, a native of Korea, was working on his master's degree. Chung later got a Ph.D. and became a professor at Rensselaer Polytechnic. He worked part time at the screw company.
Robert Barr Inc. of Virginia Beach, Va., designs screws and contracts out the manufacturing.
Barr and Chung patented the first solids/melt mixing screw, the ET (for energy transfer). Other screw designs include an improvement on the ET, called the VBET (variable barrier energy transfer).
Barr joined SPE in 1964, kicking off a long relationship with the professional association. He served for 30 years on the board of the SPE Extrusion Division. He received the division's top honor in 1996, the Bruce Maddock Award.
Barr remains chairman of Robert Barr Inc., serving in an advisory role. He lives in Coronado, Calif., and has a 40-acre ranch in the tiny Wyoming town of Bondurant. He stays busy on the ranch and does plenty of woodworking, a hobby. He has four horses, but said he doesn't ride anymore.
I've got 12 grandchildren and they keep the horses busy, Barr said.