Planning a CNC project? Discover what materials are best for CNC cutting and design in this essential guide.
One of the most important elements of any Computer Numerical Control (CNC) design is choosing the best materials for the job. The beauty of CNC machining is that you can produce parts and items from almost any wood, metal or plastic. However, the vast range on offer makes it extremely challenging.
In this guide, we compare some of the most common materials for CNC cutting and give you a run-down of what ones you should be using for your project.
Understanding the material section process
Before you can choose the best material for your CNC project, it pays to have a plan.
Firstly, you must define the material requirements – i.e. what is the purpose of the item you’re designing and what properties does the material need to have to fulfil that job? This also includes considering the environment in which the item will be kept or used. For example, certain metal materials might look out of place among your home décor if you’re building shelving.
You should select your materials based on cost, aesthetics and mechanical performance (if applicable) too. Once you understand this thought process, you can start properly exploring the types of materials to use on your CNC project.
The best wood materials for CNC cutting
One of the most common questions regarding wood materials and CNC design is whether plywood is any good for carving. While it’s cheap to buy and easy to obtain, plywood is thin and chips easily, requiring a slow process of cutting and sanding. It works for jig making and layering, but for intricate CNC cutting, it won’t give you the same quality results as thicker wood materials.
Limewood generally isn’t very good for CNC carving too as its soft and stringy components leave a lot of fur on the cut surfaces. As a rule of thumb, you want a wood material with an even consistency, tight/dense grains and top cohesiveness across the grain to avoid splitting. You’ll usually find this with stained or polished hardwoods, such as myrtle, ash, oak, walnut or maple.
Redwood is very easy to cut and holds fantastic detail too. If you can find an old piece, it’ll help you create a vintage piece with charm. Pinewood can work as another alternative for CNC cutting, however, it tends to be gummy and will dull cutters pretty quickly.
The best metal materials for CNC cutting
Metals are mainly used for CNC projects that require strength, hardness and thermal resistance.
Aluminium is one of the most cost-effective metal materials for CNC cutting, which is why it’s used to make a lot of general-purpose aircraft and automotive parts, as well as food containers. It’s easy to cut and is also quite strong considering its weight. You won’t have to worry about corrosion too, as it’s naturally protected.
Stainless steel sits somewhere in between in the cost bracket, depending on the grade. For reference, grade 304 stainless steel is usually the cheapest, 316 sits in the middle and 2205 or 17-4 is the most expensive.
Generally speaking, it boasts high strength, is resistant to corrosion and is easy to cut with a CNC machine. It can also be welded and polished for a complete finish. For premium CNC projects, brass is definitely the most-costly investment. However, it’s incredibly easy to machine, has brilliant electrical conductivity and looks wonderful on big architectural pieces. Alternatively, tool steel packs incredible strength and hardness for a low cost, making it the ideal material for low-budget projects involving making dies, stamps and moulds.
The best plastic materials for CNC cutting
Plastic materials are perfect for lightweight CNC projects and are ideal for businesses looking to make parts that are resistant to chemicals and hold electrical insulation properties.
ABS is one of the most common thermoplastic materials for CNC projects as it offers top mechanical properties, solid impact strength, high heat resistance and is reasonably easy to machine. Its low density keeps it relatively lightweight too.
For outdoor projects, high-density polyethene (HDPE) is a thermoplastic with high strength and good weather resistance. This is the type of material you’d use for piping.
Need a hand?
If you want some further guidance on choosing the right material for your CNC project, Midlands CNC is here to help.
We not only have the experience to help guide you, but we also have access to some of the finest materials for a fraction of the price, thanks to our long list of trusted suppliers.