It may seem strange to refer to a process that can produce thousands of parts as a “short run”, but the term is relative. Injection molding has always been a process centered on producing millions of identical items, and, in most respects, this is true today. With the development of technology, however, the need has arisen for injection molded parts in small quantities, while retaining the same precision and relative price advantages of conventional injection molding.
The biggest single cost factor in producing injection molded parts is the high cost of molds. These are generally cut from steel and hardened to withstand the tens of thousands of pounds pressure necessary to force heated plastic into the forming cavities. The advent of extremely hard and strong aluminum alloys and special surface treatments (thank you NASA!), however, offer an alternative to the traditional steel mold. Tools made from these materials can withstand the forces and wear of molding sufficiently to produce tens and even hundreds of thousands of parts when run on appropriate molding machines.
The advantage of aluminum molds lies in the fact that they are more easily constructed than hard steel molds, and that they can be modified with relative ease. Firedrake has facilities to produce short run molds which can produce many thousands of parts, and has the specialized machines and trained personnel capable of efficiently running either small or large volumes of parts. In the case of prototyping and feasibility studies, as few as twenty-five or thirty parts may be needed. On the other hand, in cases where the application only requires a few thousand of a part, such as aircraft or medical equipment applications, a “short run” may well be considered a “production run” by a customer.
One frequent application of short run molding technology is in the initial marketing of a new product. Rather than a huge investment in tools capable of producing millions of parts, a modest investment in short run tooling can allow an entrepreneur or inventor to produce a product and bring it to market. If the product meets with success, the revenue from the short run tool can easily pay for the investment in permanent molds, while limiting the liability if the product does not meet with immediate success. The ease of modifying a short run tool also allows rapid response to problems or improvements in design and customer acceptance that may arise in a new product.
Oftentimes products are likely to have very short product lives due to rapidly changing technology or markets. This, in turn, means that the numbers of any one product may be relatively small. Often a manufacturer will introduce a product, knowing full well that a few thousand units down the line it will be obsolete. In these cases, making a short run tool to produce a deliberately limited number of parts makes excellent sense.
Visit our “cost” page to get an idea of what various types of parts can be made, and the costs involved.