HOW MUCH DOES INJECTION MOLDING COST?
Traditionally, injection molding has been a production process featuring high initial (tooling) costs and low production costs. It has not been until the recent introduction of aerospace inspired metal alloys combined with sophisticated electronic control of machine functions that truly inexpensive injection molds, capable of serious production have been possible. Up until the late 1980s, soft injection molds, usually made of aluminum, were used for prototyping, seldom being used for more than 1000 parts. Modern alloys, along with molding machines designed to apply molding pressures more evenly and gently, have resulted in the ability to design low cost injection molds capable of running as many as a million parts. These economical injection molds can cost from 1/4 to 1/2 as much as traditional hard steel molds. At the same time that improvements were being made in machines and mold technology, the tools and procedures for rapid changeover from one mold and material to another mold and material were being developed, resulting in low cost injection molding for short runs.
Below are several examples, with prices, of injection molded items produced with economical soft tooling from low cost aluminum molds. There is a range of sizes and materials demonstrated, as well as items of different orders of complexity.
The material is acrylic, which is virtually impervious to weather and sunlight. The signs are supplied on demand, as new homes are built in the subdivision. The numbers are attached to the background plate with a special acrylic glue to form a permanent bond.
MOLDS (for plaque & #'s)---$3200.00
ASSEMBLED SIGNS (PAIR)----$5.64
This 12" long desk stand was designed to hold a replaceable advertising sign for banks. The narrow slot accepts a stiff cardboard or plastic insert which can be changed periodically to advertise the latest service being promoted or current interest rates, etc.
The bottom has been designed in such a way that it may be filled with concrete to add weight if needed to support a larger display. A depression around the bottom edge can accept either a felt pad or a strip of double stick foam tape, depending on the desired usage.
This 10 inch diameter reinforced cone cover is a squirrel excluder for a bird feeder. It also serves as a rain cap to prevent water entering the feed station.
Molded from ultraviolet inhibited ABS plastic, it is designed to give many years of useful outdoor service, while providing an attractive appearance.
This is a case in which soft tooling has proven to be useful in evaluating a market. The initial investment was considerably less than a hard tool, and allowed feedback from customers to improve the product.
These small lens caps are made from a tough, impact resistant resin having good transparency, heat resistance and low water absorption. These are molded in a 4 cavity mold for a consumer application.
Transparent and transparent tinted articles are critical, since any contamination can be readily spotted. Clean handling procedures are necessary with any type of optical product. This can extend to individual protective wrapping during post molding handling if needed.