How CNCs work
On large industrial machines, the CNC is basically an advanced industrial computer with internal motion and machine control software and a variety of inputs and outputs to control the drive motors, cutting systems, height controls, and other tools that might be mounted on the cutting machine. It takes its orders from the machine operator and CAM (computer assisted manufacturing) software, converting the orders into perfectly timed electrical signals that control all functionality. Industrial CNCs are designed to be extremely robust, to withstand long term use in dirty, rough, and electrically noisy environments; however, this robustness adds cost and complexity.
Lower cost light industrial tables often use a consumer PC or laptop as the CNC. While these computers, designed for a relatively easy life in clean, temperature-controlled environments, might be expected to have reliability issues in a harsh production environment, they are completely capable of handling the motion and limited input and output requirements on many small machines. If a consumer PC is to be used, the system must be equipped with a modern air plasma cutting system that uses a blowback torch starting technology, which produces a lower level of electrical noise interference. In contrast, older air plasma systems and industrial plasma systems use high frequency, high voltage or capacitive starting that can play havoc with delicate electronics.
When selecting a CNC, you’ll want to look for an easy-to-use interface. While many lower technology machines use a standard office keyboard and mouse to control functionality, the higher-end machines incorporate simple touchscreen controls.
CNC software should be as intuitive as possible. This is often not the case if the CNC software has been repurposed from machining processes such as routing and milling. Select a user interface (CNC software) that’s been designed specifically for cutting tends to be much easier to learn and use on a daily basis.
CNCs play a critical role in the overall success of a cutting machine operation. Ideally, a CNC should provide the user with:
- Easy operation
- Consistent, reliable performance
- Increased productivity
- Flexible system configurability
- Accurate motion and process timing
- Simplified system diagnostics
- Advanced cut process control
- Integrated communications to system and tools
- Regular manufacture software updates to keep pace with the growing needs of the cutting industry