GAIN Eliminates Hot Runners
Automotive Bumper Fascia

Conventional molding would use up to 5 gates and a hot-runner. GAIN Technologies allowed the part to be produced with only one gate and without a hot-runner. This was made possible by using "in part" runners which greatly increase the flow length of the resin. When the mold is approximately 90% full, a rotary shut off valve isolates the resin and nitrogen gas is introduced through the nozzle. Taking the path of least resistance, the gas follows the in part runners and evacuates the excess material which fills out the balance of the part. At this point, if conventional molding was used, packing out the part would be done through five separate gate locations with pressure ranging as high as 12,000 to 15,000 p.s.i.

This conventional method would create five different pressure gradients across the part, many intersecting each other. The high pressure would also create high levels of stress which could exhibit themselves by the part's instability during heat cycling. By contrast, using GAIN, the molder was able to pack out the part using only 4,000 p.s.i. "In part" runners distributed this lower pressure much more evenly across the part, even to the extremities. The result is considerably lower molded in stresses and a much more dimensionally stable part.

Mold & Process Advantages Eliminate $100,000 hot runner Shorten mold delivery by 4-6 weeks Extended mold life due to low pressure injection Lower mold cost Lower mold repair cost Less clamp force required Faster part cycle Less production down time No flash Part Advantages No internal part stresses High quality parts to size No knit or flow lines Part thickness can be reduced 20% Resin savings of 10% due to lack of mold spread No flash

USA Isuzu Dash Panel

Mold & Process Advantages Eliminate $100,000 hot runner Shorten mold delivery by 4-6 weeks Lower mold cost Lower mold repair cost Less clamp force required Faster part cycle Less production down time Extended mold life due to low pressure injection No flash Part Advantages No internal part stresses High quality parts to size No knit or flow lines Part thickness can be reduced 20% Resin savings of 10% due to lack of mold spread No flash

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GAIN Improves Many Products

Television Cabinets
A manufacturer wanted to produce television cabinets without adding plastic or metal support brackets. Prior to the use of GAIN equipment, the cabinets needed secondary operations to add the robust attachments for the Cathode Ray Tube. These attachments could not be made strong enough without causing sink marks on the Class "A" surface. With the use of GAIN equipment, the manufacturer now produces cabinets for CRTs up to 21" using one gate located at the top center with channels directing the material flow down both sides of the cabinet and using the bottom or pan as a spillover. Goldstar, for example, used GAIN equipment and a two cavity mold for a 13" CRT bezel. It runs in a 600 ton press at a very fast 45 second cycle. For CRTs larger than 21", GAIN usually recommends two gate locations at the top. While GAIN is used in a production environment for cabinets up to 52", we have recently prototyped cabinets as large as 67"

GAIN These Advantages Elimination of secondary operations to add plastic or metal support brackets Improved part integrity as attachments can now be molded integrally No sink marks on Class "A" surfaces Material savings with many parts that were previously close to 4mm now produced at 3mm-a common occurrence for GAIN produced parts is the reduction of standard wall stock Shorter cycle time due to reduction in material

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Plastic Lawn Chair
A manufacturer needed to find a quick "fix" for a plastic chair with weakness designed into the rear legs. As a general rule, we prefer working with a manufacturer from the very beginning of a project, rather than being called in to help fix a problem, however, here's how we solved the problem. To add more strength to the chair legs, a flow runner was added at a single gate location directing resin to the heavy rib sections of the chair. In addition, flow runners were added to each of the legs. When the chair was shot, using the GAIN process, tubular sections were created in each of the legs. These new tubular sections dramatically increased the part strength and solved the manufacturer's problem.

GAIN These Advantages Flow runners eliminate sink marks at ribs Increased strength in the chair legs with tubular sections in each leg Reduced cycle time due to the material removed in the heavier ribbed sections Sink free surface on the seat portion of the chair Single gate with flow runners

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Double Basin Washtub

The manufacturer of a double basin washtub wanted to improve quality, reduce cycle time and use less material. This sounded like a big order. The washtub was being molded with structural foam, using a shot size of 28.3 lbs. and taking a cycle time of 300 seconds. We experimented with various materials before selecting a 15% calcium and talc filled polypropylene. Using the GAIN system, we were able to reduce shot size by 14% to 24.3 lbs. and shave 40% from the cycle time, taking it down to 180 seconds.

GAIN These Advantages Reduced resin from 28.3 lbs. to 24.3 lbs., a 14% savings Cycle time reduced from 300 seconds to 180 seconds, a 40% savings Improved quality Eliminated part stress

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