When you commence with the appropriate information, contracting a plastic mold maker and having equipment created is a lot less intimidating. Molds can be quite complicated and costly. After the tools are made, they are essentially fixed in stone—or steel, depending on the situation. They can’t be changed because they’ve been developed and cut out of hardened steel.
Your design/architecture for manufacturing(DFM) engineer should have defined the type of plastic that will be used for your parts. Many types of plastic will need to be molded in tools made of a certain type of metal because they are not all the same.
For example, simple PP or HDPE pieces can be made with metal molds, but polycarbonate is a very rigid material. All it takes is one part hanging up during ejection and the mold closing on it to result in highly expensive repairs or, in extreme cases, the need to create a whole new tool.
To figure out how many cavities the molds can have, you’ll need a rough estimate of the number of components you’ll be producing at the start of your run, as well as an understanding of your long-term production goals. The more cavities in your mold, the more pieces it can produce in a single injection cycle.
The cost of injection molding is calculated by mold maker companies using a predetermined hourly rate per machine plus the cost of raw plastic material per unit. As a result, the more cavities your mold can produce, the more you can produce per hour, lowering your unit cost.
When a product is still in the prototype stage but requires production-quality parts in large enough quantities to justify the expenditure, a prototype mold may be required. This is frequently done to demonstrate to investors that a market exists before developing the business.
Testing a concept is getting more cost-effective as 3D-printed prototype molds become more widespread. However, keep in mind that prototype molds still cost thousands of dollars to create and can only make a small number of parts.
This is why it is critical to invest in DFM. Your DFM engineer will determine the mold sizes and complexity of the tool required, as well as communicate with the molder and plastic mold manufacturer throughout the process. When it comes to mold quotes, make sure you know what your components will do and require before sending out quotes can save everyone a lot of time and effort.
The creation of most tools might take anything from 60 days to six months. The entire manufacturing time will be determined by how quickly your mold is approved, how difficult and large it is, and how many other projects the plastic mold manufacturer is currently working on.
When injection molding pieces, hot plastic is pumped from the barrel through the sprue, or first hole in the mold, and then through runners, which lead to the cavities. These channels are permitted to cool with the part in a “sub-gated” cold-runner setup. A hot-runner system may appear ideal, but the cost and upkeep of such a system can be prohibitive. A plastic injection mold maker should be able to advise you on the same.
Because building a tool is the first manufacturing investment you’ll make, you should be aware of the ramifications it may have later down the line. The following are some frequent tool design considerations.
Tools that are semi-automatic or manually operated
A family mold is a single tool that can produce two or more pieces. Many of them can be produced with a turning sprue shut-off, which allows the operator to pick which pieces are manufactured by “turning off” one or more components. The injection mold maker should be able to advise on this based on your projects’ needs.
You must mention that all components must meet the country’s criteria when working with mold maker companies outside your country. Individual pieces can be simply replaced with off-the-shelf parts in your country, provided your plastic injection mold maker is familiar with these requirements.
Choosing the right injection mold maker company is a balancing act between estimating the needs for your project, and the quality of service(production, after-sales, and advice) from the injection mold maker. Do take the time and follow the previously mentioned considerations to keep your process as seamless as possible. All the best with your decision!