Once we have selected our CNC plasma cutting system, the table itself, the motor and transmission system, and the dust/fume/slag containment system, we have one last step left, no less important and decisive. Ultimately, we now have to give him orders to the machine so that it starts with the cutting operation as we designed it and this is achieved thanks to the choice of the appropriate software.
Faced with the complexity of the devices that make up a CNC plasma cutting machine, which seem to capture all our attention, the acquisition of a simple software could be a secondary task. But let’s not fool ourselves: it is the software that we are going to be using continuously in our daily work and it may depend on that software that our task becomes a great pleasure or a headache. Therefore, we had better choose something that works well for us, as many CNC softwares are adapted from machining processes such as milling and grinding, and are not suitable when used for plasma cutting. Software-operator interfaces designed specifically for plasma cutting tend to be much easier to learn and use in daily work.
First of all, we are going to briefly detail what CNC software consists of and how the orders given by the operator are executed.
The first thing we must do when working on a mechanized plasma cutting machine is the drawing of the pieces we want to cut. For this we use software that allows us to do it. Although drawings can be made in AutoSketch® or CorelDRAW®, the most common programs are those of the type CAD (of English, computer-aided design). The best known and used is AutoCAD®, which creates a DXF file.
Once we obtain the desired drawing we generate the so-called cut file, which will be read by the controller to start the cutting task, directed, in turn, by the controller software. The cut file consists of a simple list (called g-code) of the movements to perform and usually takes a form similar to this:
G01 Z-1,000 F100
G01 X4,000 Y4,000
G02 X4.000 Y8.000 I2.000 J0.000
The cut file is almost always in text format, uses simple commands and, if necessary, can be manually typed or modified. However, the operator must know the commands to manually enter them into the cut file. What if you don’t know how to write these types of files?
That is precisely where the software comes in. CAM (of English, computer aided manufacturing). The CAM software mainly performs the automated task of writing the cut file using the drawing that we previously made with the CAD software. That is why it is common to refer to these software as a system CAD/CAM.
New versions of CAM software, however, are much more complex and useful. In cutting applications they are often called nesting software, which is used to post-process and precisely position multiple CAD files of different types and quantities to more efficiently use the sheet metal of the material to be cut. Nesting conveniently rotates and positions parts, while generating reports covering costs, sheet metal usage, scrap, and more. In the CAM software of some current systems, almost all cutting parameters can also be automatically controlled and set, such as arc current and voltage, gas flow, cut flow settings, cut speeds and heights, pierce heights, etc., which simplifies the operator’s work, limits the formation of slag and increases productivity.
The figure below is a screenshot of a typical automatic nesting process performed by CAM cutting software.
The current versatility of CAM software means that through a series of mouse clicks we are also able to, among many other functions, import DXF, DWG, PDF or JPG type files, create entry and exit points, so that the torch start and stop cutting on the part of the plate that will later be scrapped, calculate, optimize and set the torch path, as well as provide warnings if we are about to perform a maneuver that exceeds the capabilities of the CNC.
In addition to the CAD/CAM utilities we also need a controller software, which uses the created CAM file to direct the controller to cut the part(s). Generally, this software uses G-codes and DXF files to ensure compatibility of machines with most programs. Driver software included with some manufacturers’ tables allows you to operate the table and its axes, as well as position the torch, operate and activate fixtures and tools, use different tools on the same file (for example, plasma and pneumatic marking) , set a real cut-off time to facilitate production and budget tracking, etc.
What makes the incorporation of these programs in the cnc plasma cutting machines is when the entire CAD/CAM process is fully automated. For example, some programs take an entire drawing or parts of it, find a way to nest them, and then create the cut file. Or, as is typical in the HVAC industry, simply enter the required sheet metal or duct dimensions and the software draws, nests, writes the file, starts the CNC and cuts the parts.
This video shows an example of one of the most widely accepted CAD/CAM software in the industry.
Now that we know the types of software used for cnc plasma cutting, let’s see how they are marketed and what we should take into account when making a choice.
In most cnc plasma machines In low cost, a personal desktop or laptop computer is used as the brain of the CNC control. While it is reasonable for these devices to present problems in a busy production environment, including dirt and dust as well as electrical noise interference issues, they are capable of executing the motion, limited input and output requirements of many machines. equipped with a modern air plasma cutting system. Typically, PC control is applied to low-cost, low-profile CNC plasma machines typically used by hobbyists, generic workshops, or even small industries with low production demand.
Experts recommend using cutting machines PC-based only with torches that use retraction arc ignition technology and not capacitive, high-frequency, or high-voltage arc ignition. The electrode retract torch ignition used in newer technology air plasma systems produces a lower level of electrical noise interference and works well with personal computers.
On all other cutting tables, and even high-end ones, it is highly recommended to use their built-in CAD/CAM and driver software, which is therefore optimized for those particular tables. These types of software also greatly improve the user interface by removing the use of the standard mouse and keyboard to offer touch screen controls, making the operator’s job much easier and more intuitive.
However, if we must purchase the software separately, let us always decide on the one that has multiple functions and, at the same time, is as fast as possible.
A good app for cnc plasma cutting must be able to handle intricate cut designs, automatically lay them out on the plate making optimal use of raw material and allowing manual intervention by the operator when searching for the best location, generate the necessary code for all cutting operations, allow printing of the designs required by the operator and, last but not least, to speed up the process and keep a record of the work carried out so that it can be repeated at any time in the future.
Attentive to this, the important thing is to investigate, consult, try free demos and choose the CAD/CAM software that not only best suits our requirements, but also ensures excellent cutting and production quality.