Well-suited to higher volume applications as multiple cavity moulds can have lower cost
Reasons to use
- Cost-effective method for complex mouldings
- Well-suited to small to small- and large-sized mouldings
- High accuracy of cavity dimensions, form and surface definition – resulting mouldings have sharper surface definition
- Shorter lead-time than for cast aluminium
- Well-suited to higher volume applications as multiple cavity moulds can have lower cost
- Can receive a huge range of surface finishes produced by shot peening, photo-etching, or CNC machining
- Tools can be modified to accommodate design changes.
Method of manufacture
Aluminium plate or block is machined by methods similar to those used for injection or blow mould tooling. CAM software is used to create the cavity (with moulding shrinkage added) from the supplied CAD model of the required product. As rotational moulding tools are shells with a wall thickness of about 10 mm, a toolpath is also created for the outside. In some cases the outside is machined before the inside so that stresses relieved during machining do not affect the accuracy of the cavity.
Where the quantity of the required rotomouldings suggests that multiple cavities, or moulds are required, the cost of second and subsequent moulds is lower cost than the original mould.