The most common question we hear is, “What is the cost of plastic injection molding?”.
This is a valid question and understand that not everyone has Shark Tank investors or bottomless pockets. The design and building of an injection mold could possibly be the greatest expense a new product faces in the development cycle.
Many factors come into play that directly affect the cost of creating injection mold. A reliable injection molder such as PM Plastics is able to provide an accurate estimate quickly from either a 3D CAD files, SolidWorks Drawings, sketch or with the general dimensions of your product.
- Part size — Large parts require large molds, resulting in greater material cost.
- Part design — Intricate part designs require elaborate mold designs, which generally increase the tool cost. Simple part designs require less complexity in the mold design, lowering the cost of the tool.
- Material selection — If the plastic used is volatile or corrosive, requires high mold temperatures, or contains abrasive materials such as mineral, glass or carbon fiber, the cost of the tool might increase. These factors could also impact the maintenance cost of the mold (a residual cost).
- Part tolerance strategy — Parts with tight tolerances will require additional mold manufacturing steps, which increases both the manufacturing and tool maintenance costs (residual costs).
- Annual volume — High-volume (think hours of production, not number of parts) projects need higher quality tools to provide reliable service, which increases the cost of the tool. A higher number of cavities is also associated with greater manufacturing costs.
- Cycle time — To achieve fast machine cycles, a tool needs uniform cooling throughout the cavity impression (and from cavity to cavity in multi-cavity tools). This requires well-designed tooling and higher precision build, both of which increase the tool construction cost and potentially the maintenance cost.
- Gate location — Proper gate location is critical to part quality, but tools that do not have gates at the side of the part require construction techniques that increase tool cost. Additionally, the use of hot manifold systems significantly increases the tool price but frequently lowers the part price and/or tool complexity.
- Mold cooling — The mold functions like a heat exchanger, drawing heat from the molten plastic. Uniform cooling throughout the cavity impression will yield the highest quality part and the fastest cycle time. Different cooling strategies will impact the tooling manufacturing cost.
- Manufacturing country — Cost and quality vary by country. Lower-cost tools usually have some challenges. Choose what makes sense based on your needs.
- Design/Build — A well-designed mold has lower residual costs, is easier to set up and to start, has lower reject rates and a predictable and consistent cycle time, and will perform well beyond its required life expectancy. Your supplier will provide reliable quality, cost and delivery when using a properly designed, built and maintained mold. On the other hand, an unreliable tool impedes production and requires extra time and effort to repair.