Additive vs. Traditional Manufacturing: How They Complement Each Other

Additive manufacturing, also known as 3D printing, is the process of creating a product by using 3D object scanners or computer-aided design (CAD) software to deposit layer upon layer of material in precise geometric shapes, unlike in traditional subtractive manufacturing processes that involve removing layers from a block of material to build a design. For example, cutting a metal bar into pieces is a very simple example of a traditional manufacturing process. However, with the wide popularity of 3D printing and the availability of more suitable metals, manufacturers are looking forward to applying both processes in the production line. The aim is to combine additive manufacturing and traditional manufacturing as a complementary process to offer perfect product finishing.

Below, we discuss the benefits of additive manufacturing and how additive manufacturing and traditional manufacturing can be used together to create high-quality products.

The Growing Popularity of Additive Manufacturing

Many machinists, fabricators, and manufacturers have been utilizing additive manufacturing more and more in recent years, as it provides many benefits such as less material waste. Here, we detail some of these advantages more in-depth.

Best for Quick Prototype and Spare Parts Design

The gradual evolution of 3D printing has enabled big manufacturers such as Boeing, GE, and Siemens to create complex prototype designs with ease. Siemens is using additive manufacturing technology to create spare parts for its different products, reducing the repair time to 90% in some cases. Moreover, Siemens only prints them as required, thereby cutting down costs related to overproduction and other logistics.

Reduces Material Waste

Working with a large block of titanium to produce aerospace components generates up to 90% waste. Unless manufacturers consider recycling the remnants, they simply add more operational costs in terms of waste management. The intrinsic capability of 3D printing to add materials layer by layer in the precise shapes required reduces the material waste often created by subtractive manufacturing methods that require removing excess material to create a design.

Shortens Fabrication Time

Various metallic parts made from additive manufacturing processes cost less because the time required for fabrication is drastically reduced. Complex shapes can easily be produced without having to use tools, dies, or molds. As the part is printed outside of a machine, designing complex structures, such as lattices or honeycombs, takes less time.

Despite having a lot of technological advantages, additive manufacturing cannot completely replace conventional manufacturing techniques. A part produced by additive manufacturing may still require machining to bring out the desired surface finish. Thus, many manufacturers are considering a hybrid model that utilizes both processes.

Hybrid Model: Utilizing Additive Manufacturing and Traditional Manufacturing as a Complementary Process

Hybrid manufacturing is a process that combines CNC machining and additive manufacturing, with manufacturers using 3D printing technology as a tool to expand their scope of design while leaning on traditional CNC processes to bring the desired product to the table.

So why is it sometimes necessary to combine additive machining and traditional manufacturing as a complementary process? While additive manufacturing can produce intricate geometrical shapes quickly and easily, it offers less precision than CNC machining, as the parts produced by a 3D printer are often only near-net-shape. On the other hand, it’s much more difficult to create complex shapes with traditional manufacturing methods, but these methods can hold tighter tolerances and can more easily create the desired surface finish of the product.

The below table summarizes the pros and cons of both methods.

	CNC Machining	Additive Manufacturing
Pros	Repeatable Accurate Good surface finish High productivity	Less material waste Geometrical freedom Material options
Cons	High material waste	Long cycle time Poor surface finish

Hybrid manufacturing utilizes the best of both manufacturing processes and involves applying additive and subtractive processes in sequence. For example, an additive manufacturing method such as Directed Energy Deposition (DED), which uses a laser or electron beam to melt materials as they are deposited onto a build platform through a nozzle, can be performed initially to create the part. The part can then be CNC machined to achieve the desired surface finish and tolerance.

Other popular additive manufacturing methods that can be combined with traditional manufacturing processes include:

• Powder bed fusion: A laser or electron beam is used to melt and fuse material powders to form a 3D part. While this process is similar to DED, it differs in how it deposits material.
• Metal binder jetting: Especially common in high-volume applications, a liquid binding agent is deposited onto thin layers of powder, essentially gluing together to create an object layer by layer.

All of these processes can be performed using a single hybrid machine, programmed and operated by a limited number of people from a safe distance. By implementing hybrid manufacturing using a single machine, the product or part can be printed and machined in a single setup, reducing the chance for error.

Other benefits of using a hybrid machine include the following:

• Less capital expenditure on equipment
• Faster lead times
• Less required inventory storage, saving floor space
• The ability to machine the interior of the part as it is produced, allowing for superior quality control

Your Local Metal Supplier for Additive and Traditional Manufacturing Processes

Industrial Metal Service supplies all types of specialty metals and alloys to meet your additive, traditional, and hybrid manufacturing requirements. We have a wide inventory of titanium, steel, stainless steel, and aluminum, as well as high-temperature alloys such as Hastelloy, Inconel, and Invar. We are local to the San Francisco Bay Area, and we can also ship nationwide with no minimum order requirements.