With the further integration of the global economy, the competition in manufacturing industry becomes more and more fierce. At present, the development of new products in automobiles, household appliances, electronics/communication, the light industry, and many other industries is increasingly inseparable from rapid molding technology. How to shorten the production cycle and reduce the cost has become the primary consideration of the manufacturing industry. It has become a common goal to improve the speed of product development and the flexibility of production. This guide is sharing you the differences between resin mold, silica gel mold, and steel mold.
Silicone molds, typically made of flexible rubber, allow natural and synthetic resins to be thrown into predetermined shapes. Resin molds can be used to make plastic-like parts, for manufacturing or for lightweight jewelry parts. Silicone mold provides the most versatility because it does not require a separating agent to prevent resin adhesion. Other resin mold materials include latex, gypsum, metal, and glass fiber. Softer mold materials (such as silicon and soft rubber) make it easier to pop up finished resin sheets, but rigid mold materials (such as plaster, glass fiber, metal and wood) are not easy to warp when reused.
When you create a resin mold, you can use three-dimensional (3D) objects to give the mold shape. This object is called a model. Complex resin molds are made by placing the model in a container and pouring transparent rubber around the object. After the rubber is dried, it can be cut into two pieces, each forming a mold for manufacturing half of the resin block.
Sometimes, soft resin molds may deform after repeated use. Spare molds are more rigid molds used to support flexible rubber molds during resin casting. When casting resin is added, the standby mold can prevent the deformation of the main rubber mold. These molds can be made of gypsum, fiberglass or sometimes wood.
Once the resin mold is created and the spacer is applied, the cast resin is poured into the mold for curing. Most resin molds can be used many times to make almost the same resin block, especially when used with spare molds, it can prevent deformation. Colorants can be added to remove the resin to change the color of the finished product. If added during casting, small objects or additives can be suspended and sealed in transparent resin.
Natural resins come from conifers, such as pine, birch and many palm trees. The sap of these trees is composed of volatile terpenes, extracted in a viscous state and hardened over time. Natural resins often contain impurities, and exposure to the thermal environment can be very difficult to predict.
Synthetic resins are produced by molecular polymerization, producing highly stable viscous substances similar to those found in trees. This synthetic resin has gained popularity due to its purity and more predictable behavior. The low viscosity transparent resin found in handicraft supply stores must be mixed with hardening catalyst before curing.
According to the requirements of mold material, production cost, RP prototype material, production batch, and mold accuracy, a variety of process methods have been developed. At present, the rapid tooling methods generally include the indirect tooling method and the direct tooling method. Most of the rapid tooling methods based on RP are indirect tooling methods. According to different materials, the molds produced by the indirect molding method include soft mold, bridge mold, and hard mold. Generally, they refer to silica gel mold, resin mold, and steel mold.
Soft tooling usually refers to silicone rubber mold. After the prototype made by SLA, FDM, LOM, or SLS technology is turned into a silicone rubber mold, two-component polyurethane is poured into the mold, and the required parts are obtained after curing. Bridge tooling typically refers to the epoxy resin mold that can be directly produced by injection molding. Compared with the traditional injection mold, the cost of epoxy resin mold is only a fraction of that of the traditional method, and the production cycle is greatly reduced. The service life of the die is less than that of the steel die, but higher than that of the silica gel die, up to 1000 ~ 5000 pieces, which can meet the needs of small and medium-sized batch production. Hard tooling typically refers to steel molds, that is, metal molds are manufactured indirectly, and metal molds are processed directly by rapid prototyping.
Rapid prototyping (RP) was born in the United States in 1988, rapidly expanded to Europe and Japan, and was introduced into China in the early 1990s. Rapid prototyping technology (RP) is a new comprehensive technology that uses the idea of material accumulation to rapidly manufacture product prototypes. It has been widely used in almost all industrial fields such as machinery, automobile, electrical appliances, aerospace, and military industry. It has created a new era of rapid mold manufacturing and has a broad development prospect.
The traditional cutting process is to continuously remove the excess materials from the blank to obtain the workpiece, while RP technology adopts the idea of material accumulation manufacturing, and regards the three-dimensional as the superposition of countless parallel layers with different shapes, which can quickly manufacture the crystal prototype.