WHAT IS VACUUM CASTING?
Vacuum Casting is a technique used to copy and is also known as Polyurethane casting or Urethane casting. It is mostly used in the production of a small series of function plastic parts. It uses silicone moulds to make plastic and rubber parts under vacuum. Since it is performed under pressure, it produces high-quality, bubble-free casting with smooth surfaces without any blemishes.
It is highly versatile and capable of producing, replicating, replace engineering polymers for prototypes and end-use parts. Vacuum casting services are best suited for low volume batch production when injection moulding seems more in terms of cost. A single mould of vacuum casting can be used to produce up to 50 parts before the need for re-tooling arises. This process is ideal for low volume manufacturing.
Exelus provides vacuum casting services in India and creates plastic and rubber components from silicone moulds. The parts produced by us are dimensionally accurate and precise replicas of the master pattern.
TOYS AND ARTS
HOW DOES VACUUM CASTING WORK?
Step 1: Making the 3D “Master” model
The process begins by producing a master model- typically using 3d printing- with a high-quality surface finish.
Step 2: Making a silicone rubber mould
In the second step, a silicone mould is produced by casting silicone around the master copy. This is done partially under vacuum to avoid air bubbles. It is then cured inside the oven. The time taken for curing depends on the size of the silicone mould, but it usually takes around 8 to 16 hours. After the curing of the mould, it is cut according to pre-defined parting planes and the master is removed, leaving a cavity to make copies.
Step 3: Mixing and pouring the Polyurethane resin
A two-component resin is then mixed and a pigment is added to the mixing bowl. The silicone mould is placed in the machine where the resin is poured into the mould under a vacuum to avoid any air pockets or bubbles.
Step 4: Demoulding the cast
When the resin has been cast, the mould is placed to cure. Once it is cured, the casting is removed from the mould. Any additional finishing is then carried out in the last step.
WHY CHOOSE VACUUM CASTING SERVICES?
- Multiple components can be made from the master pattern. This reduces the product design prototyping time and cost.
- The vacuum casting process uses silicone moulding that results in high-quality products as compared to injection-moulded components.
- The type of finishing that can be done using vacuum casting cannot be matched with any other technique.
- Vacuum-cast models are usually used to test the functioning and for marketing purposes.
- The end product has such good finishing that this technique has attracted a large set of audience towards it.
- Vacuum casting can be used in pre-launch product testing, making small series of housings and covers and in creating concept models and prototypes.