Starting on a new project is always an exciting time. One of the earliest discussions with your design and manufacturing teams needs to be on the cavities required for the injection molds. Which is going to be the best for your new project? Choosing between one or the other isn’t a decision that should be taken lightly. Making the best choice has many factors to it, and choosing the wrong one can hamper future flexibility, profitability, and potential growth. If you’re nervous about the choice, we’ll breakdown each choice and give you insight for which may be the better option.
The Difference Between Single-Cavity and Multi-Cavity Molds
Injection molding has been utilized for decades to produce everything from aerospace components, medical devices, children’s toys, and more. It can produce a small volume of pieces relatively quickly or produce millions of identical parts over the course of years of use. The biggest question is always how many parts should the injection mold create per cycle?
There isn’t a secret selection process to choosing between one single cavity or multiple cavities in an injection mold. Single cavity molds produce one part just as it sounds like. The multiple cavity option can produce two, three, or as many as can fit within the boundaries of the mold and/or machine being used. Choosing which is the better option has many factors that need to be discussed thoroughly before making a final decision.
The Benefits of Choosing Single-Cavity Molds
A single cavity mold can be the best option for your product depending on the situation and molding requirements. These are their benefits:
- Potentially better for low volumes as one single part will be made every cycle
- Single molds are typically cheaper to manufacture due to their smaller size
- They can be easier to design, manufacture, and keep daily quality control with
- Single-cavity molds typically have shorter lead times to produce
The Advantages of Multi-Cavity Molds
There may be a better case for using a multi-cavity mold for your new product depending on the product, the volume required, and the material. These advantages may sway your decision to choose multi-cavity mold:
- Multi-cavity molds can produce two or more parts for every cycle of the machine
- A shorter time (less machine cycles) is required to produce an equal amount of parts compared to a single-cavity mold
- Potentially a lower cost to produce a large amount of parts
- Can be used to mold multiple unique components for one assembly or many identical parts every cycle
The Downsides of Choosing a Multi-Cavity Mold
A multi-cavity mold can be the best choice for your new project, but they also come with risks that must be accounted for. The multi-cavity mold will require longer lead times to produce as each cavity must be created in the mold to exact specifications. Each cavity can provide more opportunity to make products, but you also have to realize that one damaged cavity may create a problem with the whole mold. In the case of that, your tool shop may not be able to repair just a single cavity and the mold must be scrapped and started over. To prevent that from happening, you may need to discuss making the cavities modular so they can individually be replaced or blocked from use to prevent the whole mold being sent to the recycler. The multi-cavity molds are also going to require a larger investment to create. The molds require a larger mold size typically and more time to create each specific detail on each cavity. Imagine creating one shape, then duplicating it multiple times.
Determine Your Product Demand and Market Availability First
While you will need to decide on multiple or single cavities in your mold, the first question you need to answer is based on the demand forecast and market available. How many parts do you initially forecast the market will need? What potential is available for future growth? Is the market volume subject to volatile outside factors such government import or expert tariffs, supply chain disruptions, logistical route or transportation changes, etc.? How critical is the quality of each component, and is variation between cavities acceptable? All of these questions must be answered to correctly identify which mold choice is the better option.
Conclusion
The choice of a single-cavity mold over a multi-cavity mold can be a difficult one. Your market opportunity and future forecast may dictate which is the better initial choice, but choosing one over the other without thorough discussion can be detrimental to the product long-term. At SEA-LECT Plastics we pride ourselves in tool and die manufacturing that allows us to deliver high quality products free from defects. We have multiple options for manufacturing to help your business succeed. SEA-LECT Plastics has an elite team that can discuss the available options for your new project, we produce world-class prototypes and products, and we have decades of experience with plastic injection molding operations. Our tooling experts can create molds from 3D designs and make fine adjustments to ensure smooth molding operations on a daily basis. We can offer support to determine what type of tooling you need, what materials to choose, and can support the generation of documentation to win new business in your industry. Give us a call at (425) 339-0288 or email us at mattp@sealectplastics.mystagingwebsite.com. We’ll help to determine the best manufacturing for your next project.
Matthias Poischbeg was born and raised in Hamburg, Germany. Matt moved to Everett, Wash., after finishing his bachelor’s degree in business in 1995 to work for Sea-Dog Corporation, a manufacturer, and distributor of marine and rigging hardware established in 1923.
In 1999, Matt took over the reins at Sea-Lect Plastics Corporation, a sister company of Sea-Dog and a manufacturer of plastic injection molded products with an in-house tool & die shop. Matthias Poischbeg is also a contributor to Grit Daily.