Why do people want 3D printing to replace all types of manufacturing?

I recently came across a interesting question in Quora, and I decided to assemble my thoughts in a blog post. So here's what I think...

Breaking down the question

Let’s break down this complicated question. To be adopted in manufacturing, 3D printing has to compete with technologies such as:

• CNC machining, Sheet metal fabrication, and Die Casting and Metal Injection Molding (on the metal side)
• Injection molding, vacuum casting, thermoforming and laser cutting (on the plastic side)

For greater industrial adoption, 3D printing has to beat these technologies in terms of overall manufacturing cost and/or part performance.

Let's pause for a moment...

Why does 3D printing have to compete with these established technologies? Why can't it be used in parallel?

Imagine this scenario: you are an engineer working on an exciting new piece of hardware (let's say Tesla's Model 4). You have the option to manufacture parts of the subsystem you're designing using one of three different technologies: 3D printing, CNC machining and Die casting.

How will you convince your manager that 3D printing is the way to go? How does it add value to the final product? Is it stronger, lighter, stiffer? What about cheaper? Why should we make the change?

The uphill battle for any new technology isn't just that has to be better than an existing process; it has to be MUCH better.

In my mind, this is how 3D printing competes with other manufacturing technologies. The technology and materials are (slowly getting) there. It is a societal change that needs to happen now, and this takes time.

Back to answering the question...

To fully understand why this is possible, we should consider how 3D printing fulfills the needs of three distinct groups:

1. Design engineers
2. Manufacturing/Supply Chain engineers
3. Professional end users & consumers

Design engineers

Design engineers are attracted to 3D printing for two reasons: its design freedom and its manufacturing speed.

They can take advantage of the design freedom that the technology offers to create parts that are optimized for their function. For example, they can use advanced CAD techniques like topology optimization - see the image below - to develop lightweight structures and significantly improve the efficiency of their designs.

Design engineers also love the speed of 3D printing. In fact, the most established use of 3D printing today is prototyping. 3D printing has captured almost the entire prototyping market for plastics and is rapidly expanding on the metal side.

Note that until recently that was not possible for a simple reason: the materials were different than what design engineers were used to. Certification and standardization are a must in many industries.

Manufacturing & Supply Chain engineers

Manufacturing & Supply Chain engineers are most interested in the on-demand nature of 3D printing.

The key question here is: “how can I reduce the overall production costs of my organization?” 3D printing is an ideal solution for applications in spare part production, for instance. Parts can be stored in the “digital inventory” until they are required and then manufactured-on-demand and close to the location of use. This can minimize the overhead costs and transportation costs, improving the efficiency of the supply chain.

Manufacturing where you need it & when you need it; this one of the greatest appeals of 3D printing.

Don’t forget that manufacturing with 3D printing involves only a few manufacturing steps. Some post-processing will always be required (e.g. sintering, support removal, surface smoothing etc.), but overall the process is much simpler. 20 distinct operations can turn into 4 (for instance, see this application from Milwaukee Tools )

End users & consumers

End users & consumers have already started enjoying the benefits of 3D printed products without even knowing it (most of the times). For consumers, the main benefit is mass customization.

One of the earliest commercially successful applications of 3D printing came from hearing aids. In fact, the companies that did not adopt the technology, very fast when out of business, as they could not keep up with the competition.

Another very nice example came last year from Gillette and their 3D printed razor handles. We will see more applications like this in the years to come.

How would you answer this question? Send me a message or leave me a comment below and let's start a discussion.

P.S. I recently finished working on a report on the current state of the 3D printing industry. If you want to learn more on this topic, keep an eye out for the release of the 3D Hubs 3D Printing Trends 2019. The report will be available for download here: Trends | 3D Hubs