Three-Material Molding with Foamed & Solid LSR
Negri Bossi Canbio sT press molds a ping pong paddle with hard and soft thermoplasics and both solid and foamed LSR.
On display at the Negri Bossi booth is an example of the Canbio sT servo-hydraulic toggle line (180 to 500 metric tons), recently introduced to North America. These “highly modular” machines have the Tactus controller with 21.5-in. touchscreen and energy-consumption monitor. A 180-m.t., two-shot model with a third auxiliary injector is molding a ping pong paddle with three materials (or four, depending on how you’re counting).
The rigid core of the paddle is PBT, molded on the main horizontal injector. The smaller vertical injector molds a TPU soft-touch handle. The mold is directly fed liquid silicone by an “Easy-Balance LSR” unit from Guzzini Engineering. This unit overmolds two different ball-control faces on the paddle in two densities—the firmer face in solid LSR and the “spongier” side in microcellular foamed LSR. Parts are handled by a six-axis robot from sister company Sytrama.
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