At Subcon Laser, we pride ourselves on our ability to offer our clients all sorts of different materials for laser cutting. We offer aluminium, brass1/2 hard, plastics and stainless steel among plenty of other materials. One of the materials we use most often is mild steel.

What is Mild Steel?

Mild steel contains more carbon than other types of steel, typically 0.05% to 0.25% in weight. Any more carbon than this would produce cast iron. As mild steel is not an alloy, it does not contain large amounts of any element other than iron. This gives it a few properties that differentiate it from higher carbon and alloy steels.

Mild steel is made with a combination of coal and iron melted together in the blast furnace. Once melted, the mixture is moved to another furnace where any impurities are burned off. At this point, the manufacturer may make adjustments to the mild steel’s chemical composition.

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What are the Properties of Mild Steel?

A strong and resilient material, mild steel is often used in construction as a structural material. It is relatively inexpensive, malleable and perfect for laser cutting.

The tolerance when cutting mild steel is very impressive. A piece of 3mm thickness can be cut to a tolerance of 0.1mm, a tenth of a millimetre! Even when cutting a piece of 12mm and upwards, the tolerance when cutting is 0.3mm. This means that our mild steel laser cutting is as accurate as our stainless steel cutting.

What can the Mild Steel be Treated With?

Untreated mild steel will begin to rust almost immediately but we offer a few different finishes to prevent that from happening. The grades of mild steel we usually stock are:CR4, S275 and S355 and we provide a range of finishes including:


spring steel

tread plate



Of course, if you have something else in mind, we will do everything we can to accommodate your needs!

laser cut letters

Mild Steel Letters in the Rust Garden

One of our most recent projects using mild steel was cutting letters for the Rust Garden. This was an unusual project for a few reasons. The mild steel letters would be used as a kind of gravel replacement for a path and the artists, Donnovan and Siegel specified that the steel should not be treated in any way. They were using the mild steel because it would gradually rust away.

We loved the way that the natural oxidisation process was being used to show the transient nature of the garden. Though mild steel begins with a shiny, silvery surface, the oxidisation process brings out orange purple tones, which, with the clever planting in the Rust garden made for a striking contrast.

Mild steel was the perfect material for this garden and could be just the thing you need to achieve your projects too. Get in touch with us today to find out more about our mild steel cutting services.