A Beginner’s Guide to CNC Tooling

CNC machining is a precise form of machining that can create complex and intricate designs. Precision is vital in the world of CNC and what makes this happen is CNC machine tools. There are a wide variety of tools for CNC, and it can be difficult to understand what tooling you need for your specific project. Different tools are capable of successfully completing various tasks with precision. These tools are essential to get the job done well, but they are often overlooked, and the wrong tools are used for the wrong application. If you use the wrong tool, it is easy for the outcome to be poor.

Rennie Tool is here to help with this beginner’s guide to CNC tooling. Understand the world of CNC tools so you can choose the correct one for your project and see why they are so important. Whether you are a CNC professional or a metalwork or woodwork hobbyist, understanding the world of CNC tooling helps to prevent costly mistakes, leads to very high-standard finished products, and boosts your machining skills.

What is CNC machining?

The term CNC means Computer Numerical Control which evolved from the numerical control machining process. This process used punched tape cards to control machinery. CNC refers to the automated control of machining tools, like mills, lathes, drills, routers and 3D printers. These all use a computer to make the machine work.

The process of CNC machining focuses on inputting coded instructions into CNC software on a computer. This then translates the code into precise movements for the cutting tools to follow, giving you specific shapes and designs. CNC machines let companies and enthusiasts produce accurate parts, products and intricate items at rapid speeds. This makes it ideal for intricate, complex designs and high-volume production.

CNCs can shape and design a large collection of materials such as metal, wood, plastic, foam and composite. Due to this versatility and speed, many industries use this machine for different applications, from aerospace to medical.

Basics of CNC machining

CNC machining is a subtractive manufacturing process that uses computer controls. It removes layers of material from a blank or workpiece to make a custom part. Different types of CNC machines have their own specific capabilities and applications. So, various industries need to use a certain type of CNC to suit their project requirements. Some common types include lathes, routers and milling machines.

A massive part of CNCs is the use of programmes and code. They use G-code and M-code programming languages. G-code gives instructions for the machine’s movements, directing it to where on the material it needs to go. M-code controls other machine functions such as spindle speed. To successfully create a CNC program, you need to use CAD (Computer-Aided Design) software. This helps to create the desired part design. After it’s designed on the software, the CAD file is imported into CAM (Computer-Aided Manufacturing) software. This CAM software translates the design into machine-readable G-code and M-code.

When the design is cutting, there are key factors on the machine that show you what is occurring, helping you to fix any issues. These are:

• Feed rate: Determines the speed of the cutting tool moving through the material.
• Tool change: Shows you when a new cutting tool needs to be used.
• Coordinates: Defines the position of the cutting tool.
• Coolant: Controls the application of coolant during machining.
• Spindle speed: Highlights the rotational speed of the cutting tool.

Types of CNC machines

To fully understand the world of CNC machine tools, you need to get to grips with the different types of CNC machines. Each type offers something unique to suit various applications and will determine what tooling needs to be used too.

Mills

CNC milling machines use a rotating cutting tool to remove material from a stationary workpiece. They can drill, tap and bore into materials to create a unique part or product. Mills can work by using multiple axes which gives a lot of versatility for projects. This allows multiple industries to use this machine, such as aerospace to create sturdy aircraft components.

Lathes

CNC lathes rotate the workpiece around a stationary cutting tool. By doing this, you can gain a precise and efficient shape from the material used. They are typically used for turning operations. These machines can be used with a variety of materials including metal and wood.

Grinders

CNC grinders have a rotating abrasive wheel that shapes and finishes a project. It offers precise and clean grinding, giving you a quality finished result. They are best used for making precise components that have tight restraints and tolerances. For example, making automotive parts for engines and bodywork.

Laser cutters

These use a focused laser beam to slice materials. It is highly accurate and clean, which is ideal for cutting thinner materials. This can be materials like plastic, wood or sheet metal. Laser cutters can make intricate designs and are used in many industries, such as electronics.

Routers

CNC routers are a cheaper alternative to milling machines. They cut softer materials like wood and foam, but they can still create intricate designs. These routers can provide hobbyists with a quality cut for a variety of materials as well as industries.

What is tooling in CNC machining?

CNC tooling is basically the tool used to cut, drill or shape materials in the CNC machine. They are the tools that a machinist uses to successfully complete a range of applications using a variety of materials. Typically, CNC is used for metals but can also accommodate wood, plastic and even foam. The tools used are usually stored within the tool magazine system of the machine. This is a device for the storage and tool change needed in the automated machining process. However, a few CNC machines may need to use individual collets or chucks to hold tooling in place.

CNC tooling is made to provide excellent cutting precision via various tasks. Having quality CNC tools is essential as that in itself can lead to a successful or unsuccessful finished outcome. As well as this, it also depends on the expertise of the person operating the machine.

Types of CNC machine tools

There is a large array of CNC tools available, and it can be confusing to decide which tools you need to know for which application. Understanding these tools will help you to use the right tool for the job.

End Mills

These in itself come in a variety of types. It is a tool for CNC machines that cut materials to create your desired shape. There are roughing end mills which remove large quantities of material quickly and ball nose end mills which help to create complex 3D surfaces. Ball nose end mills have a hemispherical tip that sculps the contours and smooths 3D surfaces. These are perfect for workpieces that need an intricately detailed finish.

There are also flat-end mills that have straightforward ends to make precise, flat-bottomed cuts. 5 flute end mills are another type that are made with an additional cutting edge to create a smooth finish. Similar to these, there are 4 flute end mills available which is the standard tool for general purposes.

Drills

Drills are considered tools that make round holes, but for CNCs, they are more complex. There are indexable drill bits that are efficient and versatile and are known for their replaceable cutting inserts on a sturdy tool body. They can work on many materials from soft plastic to hard metal.

There are also deep-hole drills available that can drill deeper than a standard drill bit. As well as this, there are spotting drills that are short in length and rigid and centre drills which give a dual purpose to make pilot holes.

Inserts

Inserts are an essential tool and are replaceable tips that can easily be replaced once worn or when a project needs a different cutting edge. There are various material inserts such as Carbide for exceptional wear resistance and strength. Coated inserts have layers of materials like titanium nitride or aluminium oxide to enhance longevity and performance.

Polycrystalline diamond inserts are a superior choice, giving an exceptional surface finish and unparalleled durability. While ceramic inserts cut through hardened steel, giving you unmatched heat resistance.

Reamers

Reamers are an ultra-precise tool that refines existing holes while providing an accurate and smooth finish. There are straight-shank reamers which are the most compatible with many machines because of their straight design. You can also get tapered reamers which make tapered holes bigger or finish them.

Shell reamers are great for lots of material removal or making uneven surfaces smooth while indexable reamers are used where precision is key.

CNC machine tools are vital to ensure your project is successfully complete, giving you a smooth, clean and excellent finished product. Understanding the tools needed and CNCs themselves allows you to hone your skills and develop them, offering you a world of possibilities. Ensure to choose your CNC tools carefully, depending on the application, and keep them regularly maintained so they can last for years to come.

Browse Rennie Tool Company’s selection of CNC tooling to find durable and precise tools to suit a wide selection of projects. From milling tools and drilling to router bits and turning, you can find what you need easily and quickly.