The ISO/ASTM 52900 standard, “Additive manufacturing – General principles – Fundamentals and vocabulary,” was released in 2015. Think about that: Just over 10 years ago, the standards were codified for what was, and still is, this fast-developing technology.
Conversely, the ISO 286 standard for subtractive manufacturing tolerances is one of the International Organization for Standardization’s (ISO) earliest standards. ISO was established in 1947, so we’re talking the better part of a century.
To say that additive manufacturing (AM) is still young, especially for standardized manufacturing processes and practices, is to greatly understate the case.
What’s more – or actually less – when it comes to metal-removal operations, things are comparatively simple. The vast majority of operations can be described as the tool moving (milling) or the workpiece moving (turning). This is not to overlook grinding, EDM, laser cutting, or other processes, but you can go into any shop anywhere in the world and undoubtedly see, and easily understand, milling and/or turning. With AM, things are a bit trickier.
According to ISO/ASTM 52900, there are seven AM categories, each with their own advantages and modes of operation:
Vat photopolymerization
Material extrusion
Powder bed fusion
Material jetting
Binder jetting
Directed energy deposition
Sheet lamination
What’s more – and this is really more – is AM’s array of materials. In the subtractive world, 6061 aluminum is 6061 aluminum; it all machines the same. But in AM, there are often differences. Some AM materials are process-specific, including polymers and metals; the materials are often proprietary and may not conform to ASTM or ISO standard grades.
Now, all of this may sound like I am not in favor of AM.
That is absolutely not the case. By the sixth day of IMTS 2014 – The International Manufacturing Technology Show, a functioning car was built with AM on the show floor. At IMTS 2026, we will have an expansive Additive Manufacturing Sector.
AM can be an important, beneficial tool for manufacturers – one that can provide advantages over competitors.
As mentioned, the AM space has been tremendously active over the past few years, with much of the attention on the business aspects – companies coming, companies going. But let’s put that aside. Impressive work has been performed on the chemistries of the materials, application equipment, sensors, processors, and controls in AM. This makes the tech more robust and accessible.
While finding skilled personnel is always a challenge, the Maker Movement – which took DIY and supercharged it with digital tech, collaboration, and innovation – has produced thousands of “makers” well-versed in AM. These people, as well as young engineers, simply see AM as another way to make things. And they may ask, “Why wouldn’t you use additive?”
Reasons can range from a lack of internal experience to the overall productivity that can be achieved, and that’s a question that needs to be considered more frequently than it often is.
I don’t mean to suggest that companies across the board should go out and buy an AM system – after all, with its seven categories and a nontrivial number of processes within each, deciding what type to get is a challenge.
One helpful tool is the service bureau, a third-party company with an array of machines and expertise to help determine whether a part lends itself to AM production – from the standpoints of both materials and volumes – and then produce a limited run of that part. The service bureau can help you figure things out without a capital investment.
Another challenge for companies producing AM process equipment and materials is greater commonality and consistency across those processes and materials. What you offer must meet your customers’ requirements.
The benefits of AM are great. It can more readily produce parts that optimize topology, sometimes called biomorphic design – adding material for strength where it’s needed and eliminating where it isn’t. It is organic and effective. AM can also add different types of materials for mechanical or thermal characteristics.
While AM-created parts can look fluid rather than prismatic, it can be a better solution for your customer. But the nonuniformity within processes and materials is an issue AM companies need to address.
The first commercially available 3D printer came on the market in 1987, roughly 130 years after the first commercially available milling machine and 35 years after the first machining center. So while it isn’t brand new, it is much younger than the tools the industry has long used.
Work remains to be done in the AM space, but it is being undertaken and can benefit a nontrivial number of manufacturing companies that haven’t deployed these important tools – yet. Choosing AM or subtractive isn’t an either-or question. Each offers advantages, and to be competitive, the answer is likely “both.”
To read the rest of the State of Additive Issue of MT Magazine, click here.
