Why Rotational Molding
Rotomoulding, or rotational molding is the process of forming a hollow object using a closed split mold. Plastic pellets are placed into the molding chamber, then heated and mounted on a rotational station. The rotational molding machine spins around, first slowly than faster as the pellets inside the mold melt. This causes the melted plastic to coat the entirety of the mold evenly. The heat is then turned off, and the machine continues to rotate until the plastic hardens. The product can then be removed from the mold.
Although there are other ways to shape hollow plastic pieces, rotomoulding is one of the best methods to use with larger objects, like kayaks, large plastic containers, and other cylindrical products. Surprisingly enough, rotational molding is one of the most cost effective forms of plastic molding, because few machine parts are necessary. The process is relatively low-heat, which also helps save money on manufacturing costs. Rotomolding also prevents product waste, as every piece of the plastic is used in the final design. It is easy to create a variety of different sizes, shapes, and textures of plastic products using various changes in the mold design. Of course, this kind of molding is not recommended for designs with sharp edges, as the plastic can get stuck in the crevices and produce an uneven finish. The final tooling on rotational molded products is also much less than that of plastic materials manufactured through other methods.
All of these reasons make using rotomolding a smart choice, when possible.