This post is part of our #AMneeds series and focuses on repeatability. In industrial manufacturing, repeatability is more than essential – it is non-negotiable! As the use of additive manufacturing (AM) in industrial manufacturing expands, so does this need in AM. The qualities, standards. and reputation of a brand is only as good as its weakest link and in the AM ecosystem, we want to make sure AM is not that link. The ability to achieve consistent results reflects very strongly on a brand’s reputation, but more than that, it pertains to the quality and safety of parts and products. Can AM measure up to traditional manufacturing when it comes to repeatability? How can AM repeatability be enforced?
The Old New World
The first industrial revolution prided itself on repeatability – the transition from handcrafted to machine produced set new standards for quality and consistency. The adoption of industrial production was due to a combination of cost-effectiveness and acceptable quality, both hinged on repeated production of the same part or product in the production line and optimizing this process. This was the beginning of repeatability being a core requirement. Along the way, brands saw the other advantages of repeatability: parts had more predictable characteristics and projected lifespans, one part could replace another and fit perfectly in the same place as the original part, replacements could be found in many places, and all at a highly effective price. Because there are usually costs associated with setting up a production line, customizing it to the part with molds, tooling (jigs and fixtures) and other process-related issues, the best cost-effectiveness was achieved in large volumes where this upfront cost was spread over many items. Producing a mold for injection molding, for example, without utilizing it for tens or hundreds of thousands of items is not an economically viable option. In some cases, the mold costs dictate that even millions of items should be made with it to avoid a prohibitive production cost. The mold is usually tested before starting the production run to identify possible problems or defects, which can originate from the injection process or the mold itself, but once those are addressed and the process begins the part or product will be repeatedly produced with accuracy and consistency – in large quantities. This means inherent repeatability is both due to the technology (using a mold) and due to economic considerations (spreading the upfront cost).
The 4th industrial revolution- the digital factory, and specifically additive manufacturing – has small batches, and even batch of 1, at its heart. This means repeatability can’t come from quantity. When it comes to industry 4.0, AM and the business models that derive from it (e.g., manufacturing on-demand and virtual inventory) it is key to achieve repeatability in production in a way that doesn’t stem from large batches (which create physical inventories and excesses beyond the demand). The use of digital files can help repeatability since it can eliminate some human errors and problems. When this is coupled with protecting these files from unwanted changes and taking into consideration other manufacturing variables such as changes in climate, changes in the material used and even different machines or machine settings in different locations – repeatability is achievable. It’s more complicated than it might sound: just printing the same part geometry file on different machines can cause inconsistencies, in some technologies differences in humidity at the location can affect the material characteristics of the final product, etc. When parts aren’t consistent in production it can lead to inaccurate part performance, a mismatched assembly, a flawed product or even a faulty one. Companies need to be able to produce their products repeatably and consistently on different days, in different facilities, and in different geographic locations. In order for AM to reach industrial repeatability, and for companies to adopt AM processes, all essential variables must be controlled and enforced.
Repeatable at Every Quantity
Not all 3D printing technologies are suited for industrial replicability, but in recent years a number of companies have been working to enable stable and consistent additive manufacturing. Machine manufacturers and service providers are now boasting repeatability, recognizing that this is a major need for industrial users. “We have no prototyping mission at all,” says Bruce Bradshaw, chief business and marketing officer with Evolve Additive Solutions, when talking about the company’s “STEP” AM technology (below). Evolve’s goal is to create an AM machine for scale production, for the production of 1 million pieces per year. Those kind of numbers are meant for industrial use and hinge on repeatability (and low costs, but that’s for another post). Being able to additively manufacture 1 million parts is a goal shared by the entire ecosystem but you don’t have to go to a million parts per machine to need repeatability. The aerospace and aviation industries are examples of where the need for high quality and repeatability isn’t tied to quantity. Usually, aerospace parts require industrial-grade accuracy but low-volume production. AM provides the best manufacturing method for these cases, so long as the rigorous standards aerospace requires are held. Inconsistencies can be fatal in this context so the need for repeatability is even stronger. So across the board: First-Time-Right and Every-Time-Right are both an advantage and a challenge, a challenge that the AM ecosystem is gladly taking on.
Roads to Repeatability
There are different ways to reach repeatability, efforts to support the goal of repeatability in manufacturing extend to different aspects of AM: from the obvious – machines and material stability – to post-processing, software solutions, and inspection. Qualification and validation as a parallel process to the production process is another way to reach consistent results. Materialise and GE sensing offer such a solution. According to them, repeatability is all about leveraging large amounts of data to deeply understand the hardware. Blacksmith, AI software for adaptive manufacturing by Markforged, also aims to enable repeatability (part above and imaging below). “For the last hundred years, machines have been unaware of what they’re creating and would happily waste millions of dollars producing out-of-spec parts. We’re going to fix that by connecting the machines that make parts, and the ones that inspect them, with a powerful AI,” said Greg Mark, CEO of Markforged. Here, at LEO Lane, we provide a software solution that allows AM users to enforce consistent production while securing their IP and processes and controlling the quantity of production, all with real-time tracking (come by our booth at Formnext next week for more info). This lets you prevent costly inconsistency from happening in the first place!
Repeatability vs Agility
The challenge when it comes to answering the need for repeatability in AM is providing the highest consistency while still allowing production agility and not disrupting production. This means putting an emphasis on seamless integrations and collaborations, as many ecosystem players like LEO Lane do. Up until now agility and adaptability weren’t common in conventional factories. Conventional production lines take a significant amount of time to set up, changing them between production runs or between products is time-consuming which means costly. However, in recent years even in these settings shorter runs and quicker switch overs are becoming in vogue. AM is already there, it just needs to watch out on the repeatability side. Of all the needs raised in our #AMneeds series, this one seems to be on everyone’s minds, and much effort is dedicated to addressing it. There are already some good solutions and they will need to be flexible enough to keep up with the importance of this need going forward.
What are the unmet needs you see in the additive manufacturing ecosystem? Tell us about your #AMneeds. For more insights and information follow us on LinkedIn or subscribe to our newsletter for weekly updates.