Complete Costs of Injection Molding Design, DFM Engineering Rates, & Manufacturing Pricing for CAD Services

Quality injection molding can only happen if you have accurate tooling (mold) to begin with. Although the design – of the mold – essentially follows the geometry of the product or its parts, fabricating the mold presents its own engineering challenges depending on complexity and materials, adding up to the total design cost.

Cad Crowd is one of the leading services in finding the best experts in tooling design, and we’ve collected all we know about its costs (depending on each project) into this one article.

Here’s a simple breakdown of the estimated cost of tooling design services.

🚀 Table of contents

Overview

To make things much simpler, the following table gives a rough cost estimation based on project size:

RELATED: Why prototype DFM services are useful for product design at companies and firms

You should know by now that, like all custom fabrication services, there’s no fixed engineering cost to build injection molds. The exact cost is always affected by a multitude of factors, including but not limited to size, details, complexity, materials, fabrication method, and the company you hire for the job. In general, a small mold for a simple part/design may cost anywhere from hundreds of dollars to a thousand, while an advanced build for intricate objects could cost you tens of thousands.

There are also all sorts of material options, such as stainless steel, aluminum, composites, and even plastic. Steel and aluminum are the most widely used options, as they’re known to have excellent heat distribution and dissipation properties, durability, and suitable hardness for detailed features (the ability to hold shape in high-precision corners). Hard steel is, by far, the most widely used material to build molds thanks to its ability to withstand large-volume production, whereas aluminum is both conductive and cost-effective. It’s worth mentioning that some types of modern hard aluminum (such as 2024 and 7075 alloys) are easily capable of producing 100,000 parts without any major maintenance. Some companies build hybrid molds made primarily of steel and aluminum inserts to get the best of both materials in one package.

A hard aluminum mold costs on average $3,000 for a custom yet basic electronic enclosure design or anything of similar complexity, whereas a machined steel type can go for $20,000 or more. A plastic mold, typically built using 3D-printed polymer, is the cheapest option at around $100 each.

RELATED: DFM for new product design excellence: Complete guide for company success

The engineering cost

Injection molding design services are not cheap. Apart from the engineers’ hourly rates, you also have to cover the cost of equipment usage, materials, and labor (fabricators). You don’t have to purchase an entire range of equipment just to build a couple of molds, but the fabricators can’t afford to let you use their machines (whether EDM, CNC machine, or 3D printer) for free. Well, technically, they’re using their own machines, but they do it on your behalf, so you take the bill at the end of the day.

Tooling/mold

Assuming the product parts have already been designed, it’d take around 2 – 4 weeks to build a simple mold and about 6 – 8 weeks to create a complex one. While a custom fabricator can probably take care of the design task for you, there’s nothing wrong with sending them an already-finished mold design, especially if you have the engineering team to do it in the first place. This is to reduce the turnaround time and, ultimately, cost. Furthermore, the engineers know what the final product should look like, so they’re more than qualified to design the mold for it as well. At the very least, send a CAD drawing or STL file to the fabricator to streamline the workflow.

Tooling is the main cost driver. Molds for injection molding are most commonly made using any of the following methods:

• CNC machining: a high-precision subtractive fabrication technique and the obvious choice because most molds are made of metal, either steel or aluminum. A block of raw material is secured/mounted to a fixed position and then rotated against various cutting blades, drill bits, grinders, and so on. In some cases, depending on the mold design, the material sits still as the sharp instruments maneuver around it along at least two axes (X and Y). The more advanced machines can operate on several additional axes as well.
  
  CNC machining can produce highly complex molds with intricate cavities and texturing details. The cost, excluding the materials, is around $80 per hour for a 3-axis machine and $200 per hour for the 5-axis type. CNC machines are industrial tools and should be operated by trained professionals only. The aforementioned cost already covers the labor.
  
• EDM (Electrical Discharge Machining): in case the molds are too complex, even for a 5-axis CNC machine, EDM is the answer. As the name implies, the machine shapes or cuts through metal using powerful electrical sparks. Both the workpiece (material) and the tool have their electrodes, so they’ll generate electrical discharge when in proximity to each other. Every discharge slowly builds the workpiece into shape.
  
  EDM is accurate to 1/10,000th of an inch (or about 10 times narrower than the average width of a human hair), and it hardly requires any post-processing. As long as you’re working on metals or any electrically conductive materials, EDM is one of the best tools for the job. A reputable EDM shop will charge you anywhere from $50 to $100 per hour. 
  
• 3D printing: to say that you can 3D print a mold would be a bit of a stretch, but it’s not impossible. A 3D printer is, in essence, an additive rapid-prototyping tool that allows you to build just about every shape, simple or complex, using mainly plastic-based filaments with great accuracy. It’s most commonly used in the product development process to build early prototypes.
  
  One thing to remember is that 3D-printed molds – since they’re made of plastic materials – won’t be suitable for large-volume production. If you intend to make a limited edition of a product in a very low production run, however, 3D printing starts to make sense. The cost for a 3D-printed mold would be around $200 or less for a simple design.

In terms of speed and budget, 3D printing services are the clear winner of the three. Once the STL (printable CAD file) is done, the fabrication process can start right away. Depending on the complexity, the printing process – using plastic filaments – should be done within a few hours. CNC machining and EDM take the throne for efficiency; they’re not as affordable as 3D printing, but they can shape hard metal that you can actually use for mass production.

RELATED: 5 Reasons to hire a CAD Design specialist to bring your company’s concept to market

Other cost factors

A few more variables that are directly related to the cost of injection molding design include:

• Part size: the mold has to accommodate the part to be molded. A larger mold requires more materials, so you need to consider the cost of steel, aluminum, or 3D printing filament. If you order two identically-designed molds, but they’re in different dimensions, the smaller mold will be cheaper than the larger one.
• Part design: It goes without saying that the more intricate the mold design is, the more complex the engineering/fabrication process is. A mold design has two sides: the cosmetic (side A) forms the outer layer of the product, and Side B is where you’ll find the hidden support structures. Side A is often aesthetically-pleasing, whereas Side B might be (although not always) rougher, but it’s populated by all the essential parts. You can design the cosmetic side as polished or shiny as possible and texturize in any way you want, as long as the end result doesn’t affect features and functionality. Side B must be fabricated according to the specifications. The more complex they get, the more expensive the engineering and fabrication costs.

As if to reiterate, the intended production volume determines the fabrication method. Large-volume projects definitely called for hard steel or aluminum mold. This means you have to go with CNC machining or EDM; each is more expensive than 3D printing.

Design for manufacturing vs. 3D printed molds

When you plan for product development, you expect the engineering firm to do their job with a DFM (Design for Manufacturing) approach. DFM is an engineering practice in which a product is designed in such a way that it can be mass-produced in the most efficient way possible. Cost reduction is the main goal. Over the last decade, 3D printing has been touted as the revolutionary next-generation manufacturing method to build any imaginable product easily. This is probably true in small-volume production due to the accessibility of filaments and the decreasing price of desktop 3D printers.

Mass manufacturing is a different thing entirely. You’re talking about a product designed to be manufactured in the tens of thousands, if not more. Even the most sophisticated 3D printers today can’t handle such a load, at least not as quickly as the gold-old injection molding anyway. So long as your design is intended for mass-production, your engineering team probably won’t take “3D-printed molds” into account throughout the development process because it would be counter-productive.

Cad Crowd is here to help

Here at Cad Crowd, we connect you with experienced engineers and fabricators to help you design even the most complex products and intricate molds. Whether you intend to mass-manufacture the products or have a limited production run, we have everything covered at affordable cost.

Feel free to call Cad Crowd to get your free quote.