Additive and Subtractive Metal Manufacturing

In the manufacturing of metal, additive and subtractive processes are two systems used extensively. We’re going to talk about the two distinct manufacturing methods used in metal production.

What is Additive and Subtractive Manufacturing?

Additive manufacturing can be defined as the creation of objects from the addition of materials in the form of layers whereas subtractive manufacturing involves the removal of materials that serve the creation of parts of an object. Despite their very unique modes of operation, they are used together in production based on the way they juxtapose one another.

This does not mean that you can use any process indiscriminately, however. The use of one over the other is dependent on a few factors one of which is the number of products to be made or the chronological stage of production the metal is in.

Additive Manufacturing Explained

Additive manufacturing is a system that involves the input of a material in the form of chronological layers to make a larger whole. If a layer is placed now, the layer after it must seamlessly bond with the one before it to create uniformity; this means only certain metal materials can be used in additive manufacturing if you wish to get a good product and some of these are Titanium and Cobalt alloys. The additive process is suitable for casting patterns, creating tools to be used, the development of bridges, and in the final parts of manufacturing using custom means.

Subtractive Manufacturing Explained

The subtractive process of manufacturing defines the many processes involved in the taking out of parts of a material from the whole. This can be done through the use of machines (machining), the adoption of a rotating tool used to cut metal (milling), and the formation of a hole on metal from penetration by a machine or gadget (boring). These three are prime examples of subtractive manufacturing whereas the larger metal is broken down.

The procedure for subtractive manufacturing can be done by hand or via the Computer Numerical Code aka CNC. Subtractive manufacturing is implemented in the creation of prototype metals, making tools to be used, and for metal products to be used as components to a larger whole.

Differences between Additive and Subtractive Manufacturing

There are some marked distinctions to be made between the two forms of manufacturing and they are elaborated below:

• The cost of additive manufacturing is significantly higher than that of subtractive manufacturing. It is easier to break things down than it is to build them up which is partly why the $400,000 price range for large-scale factory machines dwarfs the $2000 base price for small subtractive workshops - although the more high-tier subtractive workshops are way higher than that.

• There is very little training required when it comes to additive manufacturing since it does use a desktop printer after all - however, at the highest level, intense training is needed, but Subtractive manufacturing needs a fair amount of training to understand how to set up and maintain the machines among other things.

• Additive processes are very compatible with office spaces due to the use of desktop machines but the 3D printers do need a particular room or space with a cooling system. Subtractive processes fit in with a workshop setting at the smaller, rudimentary level, but at the industrial level, a wider area is necessary.

• Additive machines require moderate tooling and maintenance while subtractive machines require various tooling depending on the different parts and the situation.

For more information on which process is best suited to your project, whether that be a prototype through to full scale production, our expert team are on hand with advice.