SpinKast™ Silicone Mold Rubber
SpinKast™ Silicone mold rubber was developed for long lasting production molds. Made in USA with only US sourced materials and high quality ingredients, casters can be assured that these molds will outlast others. The user can pour pewter, lead, zinc alloys, resins and waxes into the finished molds.
MAKING THE MOLD:
1) The SpinKast™ mold begins as a pre-formed, uncured disk. The rubber disks have a protective poly film cover on them. This film is removed before stacking the core side of the mold inside the users circular metal frame. Stack the disks to the desired thickness. Typically, this is two of our quarter inch disks as normal molds are one inch thick.
2) The patterns being used are then arranged in a balanced symmetrical pattern to ensure even casting material distribution. Each pattern is then aligned so that material can easily flow through the cavity. Casters that have runner systems for aligning their casting parts should use these as a guide for aligning parts.
3) Once placed and aligned the parts and runner system can be embedded into the rubber. For flat parts, the patterns are typically pushed slightly into the rubber keeping in mind the parting line. For three dimensional parts, some of the silicone can be removed creating a shallow pocket to fit the part. The pattern is then inserted and the excess rubber is shaped around it to establish the parting line.
4) Insert a center plug into the middle of the rubber disc to create the sprue. Then arrange the locknuts or pins on the perimeter to ensure proper alignment and to prevent shifting. The core side is complete. Spray the core side with our TFE dry spray, dust with talc powder or mica.
5) To complete the mold, stack the additional un-cured rubber with poly film removed on top of the core side of the mold. For a one inch mold this would be two addition disks.
6) Insert the two completed halves into a pre-heated vulcanizer: 160°F (71°C) for 2 hours, 190°F (88°C) for 1.5 hours or 250°F (121°C) for 1 hour.
7) Post curing the rubber is not necessary. The post cure can be accomplished by increasing the temperature of the vulcanizer to 400°F (204°C) and curing for an additional 4 hours.
8) Allow the rubber to cool. Parts can be removed and additional vent lines, gates and runners can then be cut into the material. The rubber is now ready to receive the selected casting material.
Instructions for SpinKast™ LT Yellow & ZeroShrink