Additive Manufacturing, commonly known as 3D printing, is having an enormous impact on prototyping, and single unit and small quantity production of parts that are being used in everything from jet engines to artworks. But it not yet a significant factor in factory production. While 3D printing technology is advancing and new uses and capabilities are rapidly emerging, it will be some time before factories change over from milling machines and lathes to row of 3D printers for high volume production – if that ever happens. Here’s why.
3D printing technology is not quite ready for prime time for two primary reasons: limited materials and lack of scalability. The first 3D printers were very limited in the range of materials that they could use to make parts. That range of materials is growing rapidly and now includes many kinds of metal, ceramics, and even electronic circuits printed right on the part. This limitation is rapidly diminishing in importance.
Scalability is a much bigger impediment to 3D printing entering the world of industrial production. 3D printing takes time. It is not unusual for a single part to take hours to print and no one as yet has developed a way to change that. Sure, some new printers are faster than any machines previously available, and some are now able to produce two or more identical (or different) parts at a time, but this is still a major roadblock.
Companies like HP are making a serious effort to advance 3D printing technology to make it faster and more flexible. Stratasys recently unveiled a modular multi-printer system with three printers mounted per rack that can be installed side-by-side to make up a large-scale parallel production capability. While interesting, and probably an attractive option in limited circumstances, Stratasys specifically notes that the system is intended for “Low Volume Production and Mass Customization.”
Nevertheless, progress is being made but high volume production via 3D printing is still years away and awaiting a real breakthrough to make it a viable alternative. There are also some limitations on the size of the part being produced. The bigger the part, the longer it takes to print (and the more expensive the printer), and larger printed parts tend to be lower resolution, meaning that most larger printed parts will require further processing to smooth and finish surfaces.
As with any radical new process or capability, it will take time to integrate the new methods into the manufacturing ecosystem. One of the most intriguing features of 3D printing is the ability to produce intricate geometries that are difficult if not impossible to make with traditional material removal processes. Often, a single 3D printed part can replace a complicated assembly containing multiple parts. This substitution has to go back to the original design or be designed in from the beginning. Engineers and designers have to be aware of the 3D printing capabilities and limitations, the physical characteristics of the printed parts that result (strength and durability, wear characteristics, strain and temperature sensitivity, etc.), the cost to produce, and more in order to properly work them into the design.
The pace of change in technology seems to always proceed much faster than anyone expects and 3D printing will likely evolve rapidly as well. Every new development goes through a cycle including initial enthusiasm, a period of disappointment and consolidation when reality drains off some of the early excitement, then a period of slow evolutionary growth as the technology matures and real products and capabilities develop. Eventually those real products hit the market and volume increases to the point where prices fall and the technology can become mainstream. 3D printing is in the development stage. Mainstream is still a few years away but becoming more visible every day.