Custom injection molder and parts coater GI Plastek Corp. will hike the tonnage in its press fleet late this year when it orders a 2,100-tonner.
The capacity expansion follows a recent installation of a new painting and conductive coating line to replace the former paint line. Also due for installation soon is laser etching equipment complementing the coating operations.
The Wolfeboro, N.H., company specializes in large-part molding and coating and now runs 13 injection presses with clamps from 220 to 1,574 tons. The presses are conventional injection machines but they are also used to make structural foam molded parts, said GI Plastek vice president of sales and business development Rick Collopy in a phone interview.
Collopy said his company stands out because not only can it mold complex, large parts, it is well equipped to paint and coat them with conductive layers. The new coating line can handle parts as big as 4 feet by 5 feet. Such jobs are not unusual in its main work of molding housings for medical and diagnostic equipment, as well as components for water management, construction, material handling, recreational goods and industrial applications. Many of the parts require EMI/RF shielding. Coating such parts with copper formulations and other paints is more cost effective to protect sensitive interior equipment than including a metal enclosure in the plastic housing.
"Spray-on shielding reduces the number of parts used on instruments, eliminating the cost of a box within a box and associated attachment parts," GI Plastek said in a news release.
Collopy said GI Plastek spent about $1 million on the new coating line. It is mechanized to minimize part handling and attendant contamination, improve productivity and to get consistent coating application and drying. The line has four booths with fume hoods to cut down emissions. Priming, painting, coating and texturing operations each has its own booth and the line includes an in-line convection oven for drying.
"We installed the line because of increasing demand for painted parts," Collopy said.
Some housings and parts require two external colors. GI Plastek can mold color into the plastic and when the part is out of the mold it can mask certain areas and run the part through the paint line to get the extra color. This can be an effective way of adding logos and other decoration without resorting to in-mold labelling, often not viable for short production runs.
GI Plastek is keeping its new coating line busy on two shifts a day in a five-day week. Occasionally it needs the line for seven straight days. The firm usually molds resins that don't need pretreatment before running through the coating line. Resins such as polycarbonate, ABS, ABS/PC blends, nylon, polyphenylene oxide and polystyrene readily take to coating.
GI Plastek commissioned the coating line last fall to replace a manually operated one. The company's other services include gas assist and counter-pressure molding, assembly and graphics.
