Rotational Molding

A cost-effective manufacturing process used to produce seamless and durable plastic items, especially those with complex shapes.

Rotational Molding

Our Rotational Molding Process

This process is the choice of manufacturers in numerous industries due to its ability to produce large, hollow structures with consistent wall thickness and durability. Rotational molding can create an endless variety of shapes and sizes. Whether you want to improve an existing product offering or increase the efficiency of your manufacturing process, our rotational molding process can deliver a custom-designed product to meet your needs.

Mold Preparation

A mold, typically made of metal, is created using two or more halves that fit together to form a cavity.

Loading the Mold

The powdered plastic material, in the form of small pellets or powders, is placed into the mold cavity.


The mold is then heated and simultaneously rotated along two perpendicular axes inside an oven or heating chamber. The heat causes the plastic material to melt and coat the interior surface of the mold, evenly distributing the molten plastic.

Rotational Motion

The rotation of the mold continues during the heating phase to ensure that the molten plastic adheres to the mold walls and creates a uniform thickness.


After a specific heating time, the mold is cooled, either by air or water, to solidify the plastic. The cooling process sets the plastic into the desired shape, allowing it to conform to the mold's contours.

Part Removal

Once the plastic has solidified and cooled, the rotation stops, the mold is opened and the newly formed plastic part is removed.

Rotational Molding
Rotational Molding
Rotational Molding
Rotational Molding

Advantages of Rotational Molding

Design Flexibility: Rotational molding allows for the creation of complex shapes and intricate designs, including products with varying wall thicknesses and undercuts. This is especially valuable for industries where unique and highly detailed designs are essential.

Cost-Effectiveness & Easy Prototyping: The molds used are typically less expensive than those used in other molding methods. This makes rotational molding an economical option for small to medium production runs, prototypes, product development and testing or custom-made products.

Seamless Construction: The roto molding process produces hollow parts without any seams or weld lines common in other molding techniques. This improves the structural integrity of the final product and reduces the risk of leaks or weak points.

Durability and Strength: Creates products with uniform wall thickness, resulting in increased strength and durability. An excellent solution for manufacturing heavy-duty, load-bearing items.

Suitable for Large Parts: Can produce large and bulky items in a single piece. For example, injection molding can only produce items that are under 1.3m in volume (@ 4 ft). Roto molding can go up to 2.6m in volume (@8 ft.).

Variety of Materials: Compatible with a wide range of thermoplastic materials, allowing manufacturers to choose materials that suit their specific needs, such as UV resistance, chemical resistance or food-grade properties.

Shorter Lead Times: The simplicity of the rotational molding process often results in shorter lead times compared to other molding techniques.

Low Environmental Impact: Produces less waste and the materials are typically recyclable, resulting in a lower environmental impact.

Industries We Serve

We serve clients across numerous industries with innovative and cost-effective ways to bring their products to market.

Contact Us
  1. Agriculture

    Chemical tanks, seed hoppers, and livestock feeders/troughs, etc.

  2. Material Handling

    Pallets, containers, bins, and other logistics equipment.

  3. Medical

    Medical waste containers, specimen containers and equipment housings.

  4. Construction

    Traffic barriers, safety cones, and septic tanks, etc.

  5. Consumer Goods

    Furniture, toys, storage containers, etc.

  6. Sports and Leisure

    Equipment such as footballs, soccer balls, helmet liners, coolers and more.

  7. Toys and Playground Equipment

    Durable children's products including ride-on toys, playhouses and slides.

  8. Marine

    Boat components such as buoys, floats, and marine fuel tanks.

Our Mission

Customer peace of mind is our priority.

We achieve this goal through competitive pricing, good lead times and great products.

Gary Dickison, Bull Engineered Products

Lets Talk

Whatever your Rotational Molding needs, we've got you covered. Let us show you what we can do together.