Custom injection molding plastic can be one of the most cost-efficient manufacturing methods. There are a number of factors that play into this. These factors include: material cost, cycle time, cost for the machine, secondary operations, and the size and the weight of the part. Is plastic injection molding expensive? In most cases no! Let’s dive into the factors that affect part cost. These can help you decide if injection molding is a good choice for your project.
Contributions to Cost:
When we talk about manufacturing, and we analyze multiple types of materials, it’s easy to quickly see why plastic has such a competitive price. Plastic resin is more energy efficient to manufacture than many other materials. It also is lighter, causing transport of the material to be more efficient both due to volume and fuel efficiency. Plastic resin is also recyclable, making most materials able to be used many times over, cutting down on costs even more.
The cycle time of a mold also depends on a number of factors. The thermodynamic characteristics of the material, the intricacies of the mold design, the number of cavities, whether the part requires the manual placement of pins or inserts between mold cycles, etc. Many parts run on an automatic machine, and some even use robotics to further improve efficiency. Cycle times for small part injection molding (less than 2 lbs of material) can typically range anywhere from 15 seconds to a minute and a half.
Cost for the Machine
Cycle time, energy used, machine maintenance, and machine operator labor all play to the cost of the machine.
Many parts require secondary operations to really reach their full potential in functionality. Whether that includes EMS coating, assembly, welding, or otherwise, these secondary processes require additional materials, additional labor, and sometimes additional transport. All of these things add to the part cost.
Size and Weight of Part
The size of the part affects the mold capacity and therefore the amount of parts that can be produced in a single mold cycle. Additionally the weight of the part, along with the design specifics, can affect how long a part takes to cool and therefore affects the cycle time.
Is Plastic Injection Molding Expensive?
When it comes to plastic injection molding, the largest investment is almost always the mold development. This process includes part design, mold design, prototypes, test runs, etc.
Additionally, the mold is made of steel which makes the manufacturing, material, and transport costly. It’s for this reason, the plastic injection molding is the most cost efficient method of manufacturing particularly for higher quantity productions. A mold can last decades with proper maintenance and use. Imagine dividing the cost of the mold over the quantity of parts that will be produced by the mold. Obviously, the more parts that are intended to be produced, the more the overall cost goes down.
Is Plastic Injection Molding the Right Choice for Your Project?
Depending on your variables plastic injection molding might be the most cost-efficient option. Consider the factors we have discussed here and the quantity you intend to produce over time.
If you have a project that needs a quote, contact us today.