Plastics industry veteran Clarence Pool has honed skills in product design, tool building, machine making and polymer molding during seven decades.
He takes credit for 67 patents.
``You have to have a good imagination,'' Pool said in an interview at his home office in Pico Rivera. ``You visualize what you want and do it.''
Over and over again, he found simple ways to solve complex mechanical challenges. ``The need showed up, and I got busy and developed something that would do it,'' he said.
Now 96, Pool has diminished eyesight and hearing. Through the years, the region's surrounding orchards of avocado and orange trees have yielded to residential developments on small lots. A barn on his property served as his product development site.
He was born in the family home in Buffalo, Wyo., in 1909. ``I was always mechanical, even as a small boy,'' he said.
In 1929 he joined Douglas Aircraft Co. as an electromechanical engineer. Among other things, Pool developed flush riveting techniques, fanning aluminum angles for a tube-bending machine and, in an early polymer development, hydraulic valve packing with a compression molded phenolic retainer ring; previously, the rings Douglas made, of machined aluminum, failed cold temperature tests.
``We could not find a packing that would hold up and seal it as it should,'' Pool said. ``Everyone used a chevron packing, and I developed a chevron packaging that seals permanently and stood up'' - to minus 65° F. At one time, virtually every airplane used his solution.
He started his own business, Hydropack, in 1939 in Los Angeles, and made his own hydraulic compression molding presses, six with clamping forces of 50 tons and three of 500 tons. During World War II, Hydropack produced rubber and transfer molded plastic products for use in military aircraft hydraulics.
In a nonmilitary venture, Pool created plastic baby blocks in an era of painted wood blocks. He compression molded sets of the blocks with urea and a small prototype tool.
``I decided that was too expensive, and so I went to injection molding,'' he said. He molded the blocks in polystyrene, initially through a lone West Coast injection molder, using a 12-pocket mold with 36 interchangeable cavities cast of beryllium copper. The eventual volume: more than 1 million Cali Blox sets of 12 or 18 blocks. A full set of 18 used all 36 cavities, with three mold changes.
Other early injection molding involved terminal blocks, indicator lights and lamp-enclosed lenses for the electronics industry. In one situation, his design reduced the size of a square terminal block to sides of about 4 inches from 15 inches.
Defense contractor Litton Industries Inc. could not find anyone to build the tooling they needed, said son Richard Pool, a process engineer with medical-device maker Salter Labs in Arvin, Calif. His father helped Litton develop products that could be molded for their application, he said. ``He would be at the design level and did a lot of the mold making,'' his son said.
All three of Pool's sons continue his plastics legacy. Two head businesses begun by their father: Lionel runs the Tagit lapidary products business, and Dan heads injection molder and mold maker Cal-Tron Corp. Clarence Pool and his wife, Frieda, who recently celebrated 75 years of marriage, also have a daughter.
Though he retired some time ago, Pool keeps a keen interest in business developments and product innovations. Over the years, he developed an electronic acoustic piano, a polycarbonate viewing cup for monitoring cow milk production and the Tagit line of lapidary equipment.
The piano had the feel of a standard piano. Cal-Tron produced 22 tools for CBS Music, making piano keypads and hammers and other parts for guitars and drum sets.
The PC cup replaced a glass version and allowed a dairy farmer to remove the cup quickly so a cow's udder would not be injured in a dry vacuum pull. Some initial PC processing problems with the cup prompted a visit from GE Plastics engineers.
``They could not believe we were injection molding polycarbonate on a plunger molding machine,'' Pool said.
The Tagit lapidary cutting and polishing products emanated from Pool's longtime hobby as a rock hound. The Gy-Roc line includes Vibrahone finishing machines, the Cabber to cut and shape an oval or convex surface and the Performer trim saw. Tagit, in San Juan Capistrano, contracts for the injection molding of lapidary equipment components, including parts of Delrin-brand acetal resin for the Cabber. Pool developed the tooling.
Cutting a rock by hand might take three to six months. ``I would get impatient,'' Pool said. ``I developed a lapidary tumbler that does the same thing in six days.''
He grew his business but experienced a major setback in 1952 when, he said, the family returned from a lengthy vacation to discover several employees had absconded with the company's financial assets. Pool moved equipment into the Pico Rivera barn, kept going partially through outsourcing molding work and concentrated on tool building. He reorganized as Clarence Pool Co. and, in 1963, changed the name to Cal-Tron, his contraction for ``California electronics,'' with operations in Santa Fe Springs, Calif.
In 1979, unhappy with business conditions in Southern California, Pool opted to move Cal-Tron about 280 miles to Bishop, near the forests and recreational areas of the Sierra Nevada mountains. Son Dan ran the business in Bishop, while Clarence Pool discontinued his involvement in day-to-day operations but maintained the sales and development office in Pico Rivera, where it still exists.
Though he retired some time ago, Pool keeps a keen interest in business developments and product innovations. Now, custom molder Cal-Tron employs 17-20, operates 19 injection presses of 14-330 tons and occupies about 25,000 square feet. Cal-Tron makes parts, often with tight tolerances, for electronic, telecommunications, commercial, medical, military and aerospace applications.
Salter Labs contracted for Cal-Tron molding and tooling in the 1970s and today continues to run two molds that Cal-Tron built years ago, said Richard Pool.