Aaron Edwards' scale model of the Milacron Roboshot injection press he runs at Gorman-Rupp Industries looks real enough to shoot plastic, except that it's made of plastic - Lego blocks.
A red warning light works. The gate opens and closes. Edwards dug through his meticulously organized collection of 46,000 blocks to get everything right on the 27-inch-long model, about one-sixth scale. It took him about six months to build at home from some 3,000 Lego pieces.
``I have them sorted into different shapes and sizes and colors and stuff,'' he said.
He carried the finished Lego press into work around the middle of last year.
Edwards, 39, has been a Lego enthusiast since he was 8 or 9 years old. He is a machine operator and machinist at industrial pump maker Gorman-Rupp in Bellville. Gorman-Rupp molds polyprolylene blanks that are turned into bellows for its metering pumps, which are used in a range of applications, including photo processing and vending machines that dispense flavored coffee and hot chocolate.
The 110-ton Roboshot all-electric press from Milacron Inc. is Gorman-Rupp's only injection molding machine - well, the second machine if you count Edwards' Lego version, which sits on a work bench across from the real thing.
Edwards was a stockroom attendant when Gorman-Rupp bought the Roboshot - the Bellville plant's first-ever injection molding machine - in early 2003. He had no plastics experience, but learned quickly, and now sets up the machine and handles mold changes.
For decades, the pump maker had purchased blanks from custom injection molder GI Plastek Inc., which was located right next to Gorman-Rupp. Then GI Plastek announced it was closing the factory in late 2002. That left Gorman-Rupp with a dilemma, according to materials director James Flory, who was in charge of sourcing tens of thousands of the bellows each year. Flory contacted other molders, but they declined to quote on the work.
The bellows is a critical part that must flex over and over for the life of the pump. Gorman-Rupp employees shave down the wall thickness on a precision lathe. Then they move each blank into a blow forming process, a series of machines that heat it up, then blow air in to turn out the finished bellows.
Having the molding next door had worked well, because any problems could be solved quickly, Flory said.
The company decided to do its own molding. A team was created. They took several molds and forming presses to Milacron's plant in Batavia, Ohio, to try the processes. Larry Ramey, a Gorman-Rupp project engineer who had previous plastics molding experience, played a key role.
Initially, the Roboshot ran one shift a day, five days a week. As production increased, Edwards moved over to run the press. He photographed the press, took measurements and sketched out his Lego design on graph paper in between cycles. One minute at a time, Edwards planned his Lego masterpiece.
``I had a lot of spare time,'' he said. ``We were molding 2½-inch parts on there, and you had to actually sit there and open the door and pull a piece out every cycle. I was sitting there not doing anything else. So I drew all the plans up and measured it.''
He took the drawings home and built the model.
Now, the Roboshot is running nearly all the blanks automatically. Gorman-Rupp added a Crizaf conveyor and rotating chute, so the press can run around the clock with no operator. The machine can shut down if parts are molded out of parameters, or it can contact a technician.
In addition to Milacron, Gorman-Rupp worked with Thomas Tool & Mold Co. Inc. in Westerville, Ohio, which converted the molds to automatic eject. Many of the other PP parts for the bellows pups were tooled in Pleasant Precision Inc.'s Round Mate mold insert system, so that company in Kenton, Ohio, adapted the molds for the new press.
The Roboshot keeps busy. Flory said Gorman-Rupp made 40,000-50,000 bellows in 2006.
Edwards is keeping busy with his Legos, too, he said in an interview at the company. He walked back to his cubicle in the machining area, where a big cardboard box sat upside down on his desk. He lifted it up to reveal his latest creation, a Lego version of his childhood home.