Plastic injection molding is a highly versatile process, and it has been around for many years. Today, a range of industries use it for manufacturing, but some companies are finding prototype injection molding useful for parts required in only small quantities. Keep reading to learn more about the prototype application of injection mold tooling.
About Injection Molding Processes
Injection molding has been used in the manufacturing industry for many applications requiring large quantities of plastic parts. These can range in size from small enough to fit in your hand (plastic building blocks, bottle caps) to items as large as a chair, a storage container, or even the ductwork inside of a bus dashboard. Once a production injection mold is made, it can be used to manufacture tens or hundreds of thousands of parts.
Unknown to many manufacturers is another category of injection mold: prototype injection mold tooling. These tools are lower cost to manufacture because they use less expensive metals and do not require the long life of a production mold. If your need is in the tens or hundreds of parts, a prototype tool may make sense.
Prototype Tools Can Be Built Faster and at Lower Cost
While manufacturing Production Tooling is typically a long process (10-20 weeks from design to first shot parts), prototype tooling can be made significantly quicker and at much less cost. The timing which can be saved is perhaps the most valuable part of prototype tooling. Newer, faster CNC machining centers, some with 5-axis capabilities, contribute to this speed, as does modern 3D CAD. In addition, prototype tooling has a single cavity rather than multiple cavities typical in production molds (which allow for high volume molding) and use tool materials that are typically softer than production tooling, which permits quicker machining. This has made prototype injection mold tooling a viable method for many companies and their engineers.
Prototype tooling is often designed with optimal speed and efficiency of tool-making in mind, rather than considerations more important to production molds such as long runs, efficiency of the molding cycle, tool life, and tool maintenance considerations. These other factors are important for a tool that will run hundreds of thousands of parts and that needs to be run at the fastest cycle possible, but are not necessary at lower quantities and times where tool cost and timing are prioritized.
Easily Test Different Materials
Prototype tooling allows the development team to use production-intent materials, thereby providing the engineer the same material which is planned for later production. This is a significant difference between prototype tooling and 3D Printing Rapid Prototype machines, as many production materials, particularly recently developed formulas, are not available for 3D printing. Another benefit that prototype tooling suppliers can provide is the luxury of testing multiple materials (for example, different grades of plastic or different colors of material) without the need to run large quantities of parts in each material.
Evaluate Mold Design Prior to Building a Production Tool
In addition to testing different materials, this process also allows the opportunity to see how the part fills and look for defects such as voids, sink marks, weld lines, and other design-related issues which can be encountered in injection molding. Thus, prototype molds allow a production tool maker to evaluate their mold flow analysis and see where gating needs to be adjusted, where ribbing or radii may be required or even wall thickness adjusted in order to perfect the part. It will also bring to light design issues made when developing the 3D CAD model such as any missed interferences or fitting issues. Discovering all these possible issues during the prototype tooling phase saves significant time and money, by avoiding the need to change or modify a production tool later in the process.
Another benefit to using prototype molds when developing injection mold tooling is that it is much quicker to make changes to a prototype injection tool than to the production tool. Issues discovered with the first shots of the prototype mold can quickly be diagnosed and corrections implemented and tried out. If you had to make these changes to the production tool it would take 3 to 4 times as long, because of the complications of making changes to these molds. Injection mold cycle times and pressures can also be evaluated even though the prototype tooling has typically only 1 cavity. This can substantially save production costs thru improved molding parameters.
Gap Tooling During Start Up Phase of New Programs
Many times programs which are anticipated to be high volume programs require so many tools and design corrections that the final production tools are often not completed in the first year or two of production. A prototype injection mold tool, if properly designed, can often serve as a “gap” tool for production. Using a soft steel, rather than aluminum, and semi-automating the tools make prototype tools ideal for this purpose. If made from mild steel, these molds can still have the durability to run quite a long time.
Choose the Best Prototype Tooling Suppliers
If you are looking for the right prototype injection mold tooling, turn to Global Technology Ventures, Inc. We can help you identify the best tooling options for your application, so you can get cost-effective, timely solutions. If you want to know more, contact us today. We are always happy to help.