Rotational Molding

What is Rotational Molding?

Often referred to as ‘roto molding’ in the dip molding industry, rotational molding with plastisol is used to create hollow parts like: 

  • Disposable anesthesia masks
  • Boating bumpers
  • Mooring balls
  • Plastic doll parts
Plastic Molded Anesthesia Masks

What Steps are Involved in the Rotational Molding Process

A thermoplastic process that uses a clamshell mold to manufacture hollow plastic pieces from plastisol, rotational molding follows these steps to create PVC products: 

  1. Open clamshell mold and pour in the plastisol material.
  2. Rotate mold to heat the liquid within.
  3. As the material moves and heats, it will coat the inside of the mold, sticking to the walls.
  4. When all material has covered the walls of the mold, continue rotating until the liquid plastisol gels and fuses. 
  5. Let the mold cool.
  6. When completely cool, the mold can be opened to reveal a solid plastic piece that is hollow in the middle.

How Does Piper Plastics Rotational Mold with Plastisol?

Here at Piper Plastics, we can develop custom clamshell molds for the items our customers would like to develop. We fill our two-piece clamshell molds with just the right amount of plastisol and rotate them carefully, using multiple axes for optimal consistency.

Our unique process allows us to produce intricate, hollow parts made from PVC. For more information about the rotational molding process and other processes we offer, please contact us at 800-966-9919. 

Piper Plastics Corp. has been dip molding and dip coating items for the medical device industry since 1972. Give us a call for your next project!

See Our Process in Action

Watch how we bring precision and quality to every dip molded product. Explore our manufacturing process, facility, and commitment to excellence.

Looking to Get Started With Your Project?

Reach out to the knowledgable team here at Piper Plastics to get started on your project! We can help you plan the best course of action to make sure the job gets done right!

Frequently Asked Questions

Get answers to common questions about our dip molding services and capabilities.

Plastisol dip molding a process whereby a dipping mandrel is dipped into a liquid polymer, typically plastisol, to eventually create a solid form on the mandrel’s external surface.

We work with a variety of materials including PVC (Polyvinyl Chloride), vinyl plastisol, natural rubber, synthetic rubber, and thermoplastic elastomers. Each material offers unique properties such as flexibility, chemical resistance, UV stability, and temperature tolerance. Our team can help you select the best material for your specific application.

Dip molding offers several key advantages: low tooling costs compared to injection molding, ability to create seamless products without parting lines, excellent for small to medium production runs, creates flexible and durable products, and allows for multiple color options and custom textures. It’s ideal for protective coatings, grips, and covers.

Lead times vary depending on project complexity, but typically range from 2-6 weeks for initial tooling and first article samples, and 1-3 weeks for production runs once tooling is approved. Rush services are available for urgent projects. Contact us with your specific requirements for a detailed timeline

We serve a wide range of industries including medical and healthcare, automotive, tools and hardware, consumer products, electronics, sports and recreation, and industrial equipment. Our dip molded products are used in applications ranging from surgical instrument handles to protective caps for automotive parts.

Our minimum order quantities are flexible and depend on the specific product and complexity. We can accommodate prototype runs as small as 100 pieces, while production runs typically start at 500-1,000 pieces. We’re happy to work with you to find a solution that fits your needs and budget.

Yes! We can match Pantone colors and create custom color formulations to meet your exact specifications. We also offer various texture options including smooth, matte, textured grips, and specialty finishes. Our team will work with you to ensure your dip molded products meet your aesthetic and functional requirements.

Absolutely. Our experienced engineering team provides comprehensive design support including material selection, mold design optimization, prototype development, and design for manufacturability (DFM) analysis. We work closely with you from concept to production to ensure your dip molded products meet all specifications and perform as intended.

Still have questions?

Our team of experts is ready to help you find the perfect dip molding solution for your project.