During high-volume injection moulding, multiple copies of the same part can be made using the same mould, speeding up production times and reducing tool time for the manufacturer. It may also be more convenient for the consumer, as multiple parts can be shipped and stored together, reducing the risk of missing or incomplete sets during shipping to the customer.
Initially, the manufacturing of mirrored parts was undertaken to produce individual parts that were exact duplicates of each other. This has now changed and parts can now be made to hinge or interlock with each other, which allows many more permutations on the mirror theme, but at the same time reducing production time and cost – principally the cost of producing separate moulds for each separate part.
It is common for plastic boxes or other hinged items to be produced in this way as a single part, with either a hinge mechanism connecting the two parts together or a simple crease in the plastic separating the two halves. Similarly, the production of plastic parts for model kits is suitable for mirror manufacturing, as each part is conveniently held together by the runners and sprues to prevent loss and aid packing. It is also a convenient way of manufacturing opposing parts, as each side is mirrored by each other in the mould, allowing more complicated two-part pieces to be manufactured together.
On the downside, more runners and ejectors are required for mirrored parts and this takes away some of the space in the mould which is a problem if the required parts are on the larger side. This is generally not a problem for small parts, which mirrored parts usually are and it should be looked at if this is the market that you are intending to manufacture for.
NICE Rapid are experts in rapid tooling and manufacturing – please do not hesitate to contact us when thinking about your next project.