ELI5: 3D Printing
Photo by Gavin Allanwood on Unsplash
When you transform a block of metal by rolling, cutting, milling into a beverage can, you’re doing what is known as ‘subtractive manufacturing’. You subtract from the material to get to the desired structure you want. This is how manufacturing has been done by humans since the Stone Age.
3D printing is “Additive” manufacturing
When you build a structure with legos, you add them layer-by-layer, one on top of the other. 3D printing works similarly. Materials (typically in a thick fluid form) are layered to get 3D dimensional structures. If you remember CDs (compact discs), imagine stacking them one on top of another. You would get a nearly solid cylinder with a narrow tunnel running through the center.
3D printing was in use as early as 1980s, but the cost of 3D printers made the process unviable for any real commercial use. This changed in 2009, when the patent for a commonly used 3D printing technology (fused deposition modeling) expired, and there was accelerated innovation leading to low-cost printers. Today, 3D printers that can produce industrial goods are far cheaper than many machines used in manufacturing. Also, they’re versatile - a 3D printer can produce many different kinds of parts, whereas industrial machines are specialized for specific parts, and even specific steps in the manufacturing process for a part.
This is one of the key reasons why 3D printing can have significant impact. In making specialized parts such as automotive engines, solar panels, battery packs, companies first need to develop the right ‘tooling’ to build that part. This requires specialized, design and engineering and is itself a time- and resource-intensive process. 3D printing eliminates the entire ‘tooling’ development process. With the right printer, software and materials you can go from a 3D model to a completed part in a few hours to a few days, depending on part complexity.
Further, 3D printers now exist for a wide variety of materials - synthetics (plastics), metals and alloys, and even biomaterials. Well-known companies across the globae are now integrating 3D printing in their manufacturing processes.
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Fun fact:
The walls for ICON’s House Zero - a 2000+ sq.ft. 3D printed home were printed in 10 days.
Where 3D printing wins:
Rapid prototyping.
Earlier, parts designed digitally were produced in small quantities to check whether form and function was as intended. This process could take weeks - designs would be sent to a supplier, the supplier would manufacture and ship back the parts. And the time taken would compound with repeated iterations to get the part just right. With digital manufacturing, the entire process can be completed in less than a day.
Making Complex shapes with difficult geometries.
With traditional manufacturing processes, designs must often be made more “realistic” - the design must be one that can be produced by an industrial machine or can be cut or milled. This is no longer necessary. Infact, with digital manufacturing, designers can often ask a computer to design the optimal shape for a particular function and not surprisingly, a number of ‘biological’ geometries are emerging. This screenshot from the video by Veritasium shows a shell-like structure that is actually a part of Relativity Space’s upcoming rocket Terran R.
Producing close to where parts are consumed.
Manufacturing supply chains can span several countries where components are made in one, shipped to another, and the final product may be used in a different geography altogether. With 3D printing, components can be produced near the destination of final use as manufacturing in large scale facilities is not required. In Logistics, 3D printing is being called the ‘fourth modality’. Earlier, you could send stuff by air, sea or ground, but with 3D printing you can send it through the internet!
Make many different kinds of pieces, not just many of one kind of piece.
“Economies of scale” in manufacturing are achieved with making one kind of a product in large quantities - once you have the right production machinery and molds have been made, the incremental cost of producing more units of the same kind of piece is lower. With 3D printing this is not the case, as material costs remain steady for every new piece produced. However, the same machine can produce several different kinds of components, bypassing the need for very specialized machines. You can ‘print’ entire products, not just parts, with a 3D printer.
Lean inventory models.
Industrial facilities keep round-the-clock inventories of crucial machine parts to account for damage, malfunction, end-of-life and other incidents. With 3D printing, these facilities need to store only digital scans (3D models) of the parts they need and can print these out as required. This is resource and capital efficient, and definitely great for the planet too! (UPS - one of the largest Logistics providers for industries is building a global network of 3D printing services to counter the anticipated disruption to their business from this new kind of lean manufacturing that is emerging)
Combine many parts into 1, making components lighter and stronger.
Often complex components in a machine (including in airplanes and automobiles) are made up of several parts screwed together. With 3D printing these parts can be printed as single structure - this reduces overall weight needed and has more integrity as a single structure. Lighter parts reduce the overall weight of the machine, making it more energy efficient. It is estimated the over the 30-year lifespan of an aircraft, 1kg less weight can save half a million litres of fuel.
Reduce waste
3D printers produce very less waste when manufacturing, compared to say an industrial process where upto 90% of a block of metal may be ‘wasted’ to get the desired part. This is great for companies and for the planet.
USA launches AM Forward
The Biden administration has launched AM (Additive Manufacturing) Forward - a public-private sector collaboration to enhance adoption of additive manufacturing by manufacturers in the USA. At the early stage, this involves a commitment from companies such as GE Aviation, Honeywell, Lockheed Martin, Raytheon, and Siemens Energy to make commitments to procure additively manufactured parts in building their products.
References:
Article - With Additive Manufacturing, no tooling is required
Press release - Biden Administration Celebrates Launch of AM Forward and Calls on Congress to Pass Bipartisan Innovation Act
Article - Fast Product Development in Commercial Vehicle Manufacturing with 3D Printing
Video + Article - New 3D printer uses rays of light to shape objects, transform product design
Video - Additive Manufacturing in the Digital Era - Vestas x Markforged
Video - What is 3D Printing? - Institute of Manufacturing, University of Cambridge