Combining Additive and Subtractive Techniques for Hybrid Manufacturing

For many years, additive manufacturing seemed like it was going to be the future of all manufacturing industries. Most of this can be chocked up to hype around the new technology. In reality, the future of additive lies in a hybrid manufacturing system, one that combines additive and subtractive techniques for ultimate optimization.

When we look at the future of this hybrid manufacturing, we must split it into two different categories: machines that can operate through both additive and subtractive, and parts that are made with both additive and subtractive manufacturing. Focusing in on what I mean by these differentiations, let’s look at the latter.

Technology exists to 3D print metal parts and technology exists to machine metal parts. We know this, but the combination of both processes optimizes each technique and puts them together. As one example, femtosecond lasers are being used to additively manufacture tungsten parts while then refining the shapes through subtractive manufacturing, according to a paper published in Physics.Femtosecond lasers are essentially high power short length laser pulses that can heat or melt a metal quickly, without causing damage to the surrounding areas. This technique has been used to make high strength tungsten gears and researchers are exploring further methods.

The other combination of additive and subtractive in part production that we must examine is more traditional. This process involves laser deposition welding, a common metal additive technique. When the part is designed roughly through laser deposition, the CNC machine then transitions to milling the part to achieve higher surface finish and tolerance, according to Additively. It is this technique that shows more promise for the hybrid industry. It allows machines to incorporate typically additive features like internal lattices and cavities, with the high surface finish and precision of machining and milling. It is essentially the best of both worlds combined into one process.

Now that we understand hybridized part production, let’s look at some ways machines are combining additive and subtractive. If you run a machine shop, you likely have times where many of your rather expensive machines are sitting idle. One way that companies are seeking to overcome this is by integrating 3D printing heads into the CNC machines themselves. In other words, your CNC machine can instantly become a state of the art 3D printer, according to

If you run a machine shop, you likely have times where many of your rather expensive machines are sitting idle. One way that companies are seeking to overcome this is by integrating 3D printing heads into the CNC machines themselves. In other words, your CNC machine can instantly become a state of the art 3D printer, according to ASME.

Integration of 3D printing heads into CNC machines usually is only done to increase the usability of the machine, not create parts using both techniques. A more refined use of this technology would allow you to quickly print a model of a part, understand how it would interact, then decide if you want to move forward with milling the part out of metal. It keeps shop owners from having to operate both 3D printers and CNC machines – it incorporates both technologies into one.

As you can likely see, the combination of both techniques into either singular machines or even singular parts allows us as engineers to have a greater freedom in our designs. These hybrid techniques only open more doors to potential manufacturing.

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