We can perform many operations through Additive and Subtractive manufacturing procedures. Both forms of methods are generally used in various industries. We use them to manufacture high precise and complicated parts and components. We use CAD (Computer-Aided Design) software for Additive and subtractive manufacturing.
The basic principle of Additive and Subtractive manufacturing is different from each other. In this article, I will debate the basic working principle of both methods. And will describe that how they are different in fundamentals. I will also discuss the use of Additive and Subtractive manufacturing in industry and their operations.
Additive Manufacturing:
Additive Manufacturing is the process of building a component by adding material layer by layer to form the desired shape.
Working Principle:
3D printers are essential for additive manufacturing. So, additive manufacturing is also called 3D printing. 3D printers operate by printing layers of material on one another, and each successive layer bonds with the preceding layer. This bonding repeatedly layers over the same area and continues to form the desired part.
This function of repetition is also called fused depositional modeling. Contrary to its term, we print each layer in 2D cross-sectional layers. The same are generally stacked upon one another in 3D printers. CAD software generates programs to create parts in the additive manufacturing method.
We can use powder or ink to generate marks on paper in 3D printers. These elements are not enough in building a 3D design. Thus, in each layer we can found;
- Molten thermoplastic
- And fused using adhesive
- Or ultraviolet light.
Thermoplastics used in these 3D printers become liquid when heated due to their ability to soften against heat. But, they return to solid form while cooling. During the process of 3d printing, we program the machine to wait for each layer to cool before printing. The next layer has to achieve the required design parameters.
Operations performed through Additive Manufacturing:
We can perform a range of complex and versatile operations in Additive manufacturing. CAD models provide a vast variety of manufacturing designs developed through 3D models. In this way, we can manufacture intricate and finished components. These are unable to produce through other manufacturing procedures.
The cost of CNC machining projects is lower in additive manufacturing than in other methods. It is ideal for the manufacturing of tooling and casting patterns. Some specific operations in Additive manufacturing are;
- Stereolithography (SLA)
- Material Jetting
- And Electron beam melting (EBM).
- Materials used in Additive Manufacturing
Common materials used in this method are plastics and standard and engineering thermoplastics. Materials are generally used depending upon the nature of work and required application. So, a limited range of metals also used in specific operations in some industries in China.
Subtractive Manufacturing:
Subtractive manufacturing is the process of creating a component by;
- Removing material from a blank
- Through controlled machining and programming.
- Working Principle
The Subtractive manufacturing is a material removal process from a blank through a cutting tool to create the desired part. The blanks usually consist of solid blocks, rods, and bars of different materials. This process is performed on a CNC machine by;
- Manual codes
- Or well-defined programming through CAD software.
There is a need to process the solid or raw blank on a CNC machine to get the desired shape through cutting, boring, drilling and grinding. A virtual model designed through CAD software guides as input to the cutting tool. This model is a program of controlled instructions generated through CAD software. China is famous in CNC market that is providing best machining services.
We can also input some short programs manually into the machine. These instructions direct the machine to make the necessary cuts. These are also important for features on the blank to achieve the desired shape. Through this program, we can also control the speed of the cutting tool and the feed rate of machining during the material removal process.
CNC machines work in different ways, and in this way, they can perform many operations. A rotating cutting tool introduced to a moving material to make the desired shape in CNC Milling. Meanwhile, a still cutting tool cuts a rotating workpiece in CNC Turning.
Operations performed through Subtractive Manufacturing:
CNC machines work in different ways to get the desired shape. And we can perform various operations in Subtractive machining. A rotating cutting tool introduced to an unmoving material to make the desired shape. Meanwhile, a still cutting tool cuts a rotating workpiece in CNC Turning. Thus, versatile operations performed in this method depending on;
- The workpiece
- And material.
Subtractive manufacturing generally used to manufacture;
- End-use parts
- And tooling in auto-mobile and engineering industries.
They are preferably used for procedures that need fine tolerances and difficult geometries. Turning, Milling, Drilling, Tapping, and EDM are common processes performed in subtractive machining.
Materials used in Subtractive Manufacturing:
We can machine many types of materials in subtractive manufacturing. Generally used materials are;
- Soft and hard metals
- Aluminum
- Cast iron
- Plastics
- And thermoplastics.
Depending upon the need, wood and acrylic also used in some industries.
Final Words:
Subtractive and additive manufacturing are suitable for different purposes and have their benefits. There are some limitations in Additive manufacturing. There is no use in engaging a 3D printer to manufacture a workpiece meant for CNC machines. Although they are less expensive, they are slow in production in the case of mass production.
The basic need for each layer of material to dry causes a time delay which affects the machining time. So, CNC machines can perform many functions simultaneously in a quick time. They are ideal for mass production and versatile operations on a single component.
We can use many tools on a single machine, enhancing the machine’s productivity and efficiency. CNC machines and Subtractive manufacturing are more productive, efficient, and ideal for industrial procedures.
