Advantages of 3D printing tooling and moulds for casting master patterns:
- Reduction in high tooling costs
- Dimensional accuracy and stability of parts
- High casting yield
- Faster production and weight reduction
- Ability to reiterate designs quickly and easily
- Designs that can be printed overnight compared to weeks with CNC machining tooling
The most common casting master applications are sand-casting, investment casting and urethane moulding.
Sand-casting
Produce sand-casting tools and moulds for low-run part production, saving time and costs.
The mould is 3D printed using SL technology and then mounted into a box or board. Sand, the moulding medium, is mixed with a binder then packed around the mould which is filled up and packed tightly.
When the mould is removed from the board it is left with a negative. Molten metal is then poured into the negative and then once set, metal parts are produced.
3D printing patterns compared to traditional CNC machining allows manufacturers to design intricate and detailed parts due to SL technology printing patterns with greater accuracy and detail. Designs can be quickly iterated and reprinted in hours or overnight offering manufacturers greater flexibility.
Lead time is significantly reduced, waiting days rather than weeks to produce the final part. There is also an estimated average 70% cost savings with 3D printing patterns compared to traditional methods of CNC machining to create functional moulds.
Investment casting
3D print complex designs quickly and efficiently compared to expensive traditional foundry methods.
With investment casting, a master pattern would usually be sculptured, machined or moulded in either wood or wax. The master pattern is then sent to a foundry where it will be encased in ceramic to create a mould. Once it hardens, molten metal is poured inside the mould and once cooled, the ceramic is removed to produce the final metal part. The wood and wax is then burnt out inside to create the mould. This process of creating the master pattern could take weeks or even months to produce.
Stereolithography (SL) 3D printing technology is an alternative solution which brings costs and time savings to manufacturers. Users can 3D print master or sacrificial patterns with more complex designs, quickly and easily compared to traditional methods. Using SL technology, master patterns can be produced with a nearly hollow structure with internal honeycomb, lattice structure and thin walls. This results in benefits such as weight savings and reduction of ash when the master pattern is burnt out.
Urethane moulding
Print highly accurate and precise master pattern designs for urethane moulding – fast.
The master pattern is cased in silicone rubber to create a mould that is then used to manufacture small quantities of polyurethane parts. This application is a cost and time effective alternative to traditional methods of manufacturing.
The SL printed master pattern is cased in liquid silicon around the master to create a mould. Once the mould hardens, the master is removed. The mould is then filled with liquid polyurethane and placed under heat and pressure to cure.
Traditionally masters are CNC machined out of wood, metal or plastic. This process can take many weeks to produce and can be very costly. SL technology allows manufacturers to develop highly complex designs that can be difficult to produce using traditional manufacturing methods.
