However, don’t let that put you off, because whilst it may be difficult to become a CNC expert, it may not be so difficult to learn the basics of CNC machining which could allow you to complete a project or even land you a CNC operator job. You may not even need to learn it at all with services such as Geomiq’s online CNC machining service.
CNC Machining and What it’s Used For
Before we dive into what skills you’ll need to learn and how hard it all is, you’ll need to know some basic theory behind CNC machining.
CNC Machines are high-precision electromechanical devices that can manipulate cutting tools around 3 or 5 axis through a computer program to make complex parts. CNC Machines can be controlled by either writing the g-code for the machines, using a CAM (computer-aided manufacturing) software that automatically writes the g-code from a 3D computer model or through conversational programming which is done at the machine.
Like most machining processes, CNC machining is a subtractive process meaning that it removes material to make the desired part, unlike additive processes such as 3D printing. The machines remove material from blocks of material (called blanks) by drilling, lathes, and milling and can change tooling and bits during machining.
CNC machines can be used on a variety of materials from ceramics to polymers but are more commonly used on wood and metals such as aluminum, steel, and titanium. These machines are much quicker and more precise than manual machining methods with tolerances up to ±0.001mm! Which is far less than the width of a human hair, or about 27500 times smaller than the width of your average banana – if you’re interested…
What Skills are Required for CNC Machining
There are two areas that you must understand and be proficient in to be a good CNC operator. That is to understand the mechanical functioning of the machine and to be able to control the machine through programming.
CNC Machine Knowledge
Understanding the mechanical functioning of the machine can have a big impact on the quality of the finished part both aesthetically and structurally. Understanding the functioning of the machine includes knowledge about: tooling; feed speeds; how to calibrate a machine; how to secure work in the machine; and most importantly, how to safely operate the machine.
These skills are often overlooked as being simple principles, whilst they may be easier to learn in theory than g-code, it may take years of experience to know, for example, what type of vice will be best to use to secure a piece of work in the machine for the job being programmed.
Common CNC Machine types:
3 Axis Machines:
Multi-Axis Machines:
- Mill Turning
- Continuous 5 Axis
- Indexed 3+2 Axis
CNC Programming Knowledge: G-code and CAM
Like most people, you might find the thought of having to learn how to program or code a bit daunting. However, manually programming a CNC machine job is uncommon with the development and widespread use of CAM software. As mentioned earlier, CAM automatically writes the g-code for 3D computer models. So if you’re a hobbyist using a CAM software like Fusion 360 with an Arduino CNC machine, you may never have to touch g-code.
Even if you did have to learn g-code, whilst it is difficult to start with and to master, in a relatively short period you can be programming CNC machines. And to put g-code into a wider programming context, it is regarded as one of the easiest programming languages to learn.
As a professional CNC operator, you will work mainly with CAM. However, that is not to say that it will be easy at this level. CAM requires the operator to have expert knowledge of the machine being used and the right tools to use for the job.
Changing between different CAM software can prove to be a steep learning curve. And whilst CAM is a great tool that has increased the efficiency of the CNC machining manufacturing process, it is still often the case that CAM does not produce the desired result and the g-code has to be edited manually by the operator. This is why learning g-code is highly beneficial.
Popular CAM Software:
- Fusion 360
- Solidworks CAM
- Mastercam
- Solid Edge
- CAMWorks
Summary
So as we’ve discussed, the CNC machining process can be challenging to master but it is certainly not out of your reach. You should expect it to take over 3 years of hard work to master but it can take just a few hours of easy tutorials to create basic parts. Like most skills, CNC machining is a skill that is built upon through experience and trial and error.
If you are looking for a career in machining, despite automation in manufacturing, CNC machining is here to stay so is a relevant and valuable skill to have, and if you become a professional machinist you will likely have a rewarding and well-paid career.