Plastic parts made by rotational moulding are typically on the large and very large end of plastic products, such as the water tanks we designed for Formit Services. The moulding process is slow so it is good for moderate volume production and tooling relative to the size of the part is quite cheap.
Rotationally moulded parts, being typically large and bulky to ship, are one of the areas of manufacturing where local manufacture competes effectively cheap offshore labour and imports.
As production numbers for you product increase it is often well worth reconsidering your manufacturing approach to ensure it is the most efficient for your production numbers. Rotational moulding is often a good transition from GRP and fabricated sheet metal products and can allow much greater freedom in design – the Police prisoner wagons we designed used rotational moulding to replace the traditional canvas and steel mesh cages and are a good example of the advantages of reevaluating fabricated construction as higher production volume justifies more investment in tooling offset by savings in skilled labour.
At neo industrial design we like rotational moulding a lot, but only use it where appropriate – ask an industrial designer if not sure it’s right for you.