One of the most common causes of CNC machine crashes is faulty or incorrect code. Before you run your program, you should always check your code for errors, typos, or missing commands. You can use a code editor, a simulator, or a dry run to verify your code and catch any mistakes. You should also make sure that your code matches the specifications of your machine, tooling, and material. If you are using a CAM software, you should also check the post-processor settings and the generated G-code.
Thoroughly checking CNC code is crucial to preventing machine crashes. An often overlooked yet equally vital step is investing in employee training, specifically in understanding G-code. G-code, a series of instructions that guide CNC machines, can be intricate and challenging to decipher without proper training. By ensuring that your operators and programmers are well-versed in reading and interpreting G-code, you empower them to identify and rectify potential errors before execution. Comprehensive training, including simulations and practical workshops, can significantly reduce the likelihood of errors, leading to smoother operations & minimized downtime. Together, vigilant code checks & adept personnel form a defense against CNC crashes.
Add elements of in-process control. I,e comprehensive probing routines to detect misloads and to automatically set work offsets etc. as an addition to this, code should be verified/interrogated for and errors using a number of techniques.
If you are running large complex parts, it can be very time consuming to single block. To avoid this downtime, you really need to invest in an offline machine tool program simulation software that can catch most programming mistakes.
Always verify your part programs using a backplotting tool. This comes standard with CAM software. If you are writing code longhand there’s plotting software for that as well, both free and paid versions.
Preventing CNC machine crashes starts with proper setup and programming—double-checking tool paths, speeds, and fixture positions is crucial. Regular maintenance, including checking for worn parts, also reduces the risk. To recover from a crash, immediately stop the machine, assess damage to the tool and workpiece, and recalibrate if necessary. Always analyze the root cause to prevent future crashes.
Another important step to prevent CNC machine crashes is to set your offsets correctly. Offsets are the values that tell your machine where to position your tool relative to your workpiece and your coordinate system. You should always measure and enter your offsets accurately, using tools like edge finders, probes, or indicators. You should also double-check your offsets before you start your program, especially if you have changed your tool or workpiece. If you have any doubts, you can use a jog mode or a single block mode to test your offsets.
Use a gage that is your longest tool to set offsets rather than using the spindle face. This way, any mistake results in the tool being too far away from the workpiece or fixture rather than crashing into it.
Verifying your offsets by calling that tool up at a known diameter is helpful as well. A big thing that will save you is writing down your offsets on an offset sheet for each axis for that specific tool number. Before running verify the offset matches what’s on the paper within reason and this will save you some trouble.
Sometimes, CNC machine crashes can happen because of excessive or inappropriate feed and speed rates. Feed and speed are the parameters that control how fast and how deep your tool moves through your material. If your feed and speed are too high, you can cause overheating, chipping, or breaking of your tool or workpiece. If your feed and speed are too low, you can cause rubbing, dulling, or deflection of your tool or workpiece. You should always use the recommended feed and speed values for your tool, material, and operation. You can also use a feed override or a spindle override to adjust your feed and speed on the fly.
Every time you run a new tool for the first time the speeds/feeds might need to be monitored. When programming your first part it’s advised to use the lowest SFM recommended by the tooling manufacturer. At the machine always turn rapids down as you approach the part and watch your Distance-to-go on your control.
When the machine runnig. - Once you have created a good product, anything can go wrong. So monitor the machine throughout the process and once you leave, understand what the next tool is and activate the "option stop" function - Check the product whenever you have time even if there is no requirement to check because the quality of the product can indicate the next trend of change and the risk of failure. - Another experience to consider is the maintenance of the machine, a poor maintenance occurred an accident when the tool was not released when changing due to the main shaft oil being depleted
Even if you have done everything right, CNC machine crashes can still occur due to unexpected or unpredictable factors. That is why you should always monitor your machine while it is running, and be ready to stop it if you notice any signs of trouble. You should pay attention to the sounds, vibrations, and movements of your machine, as well as the condition of your tool and workpiece. You should also use the emergency stop button or the pause button if you need to stop your machine quickly or safely.
Excellent advice. Even on proven programs things can happen. Personally I single block and op stop my first piece ever time. I look to make sure the tool is going to the projected coordinates before it gets there to helpinimize errors. After my first piece is inspected/completed, I allow production to run and monitor sounds and spindle loads to prevent possible incidences.
I usually single block and check distance to go as I run for the first time. Checking tool tables and z heights. Also feeds and speeds. I never trust no one not even myself. Once the tool path has been proven then I go still slowly just to check loads and chips being generated by the tool
Rapid feeds and cutting feeds make sure are dropped until first piece comes out. I always lift or drop my work offsets or lift your work shifts see is what is supposed to do.
é sempre importante verificar todas as alturas das ferramentas se est?o corretas, o zero pe?a se também está correto, e simular o programa antes de rodar ele. Algumas ocasi?es, rodar o programa em uma altura de seguran?a acima da pe?a também pode auxiliar na visualiza??o do percurso da ferramenta. A utiliza??o do método "bloco a bloco" é uma op??o viável e muito útil para companhar o trajeto da ferramenta de maneira mais lenta e gradual!!!
Check offsets quiet often to make your job is precise, while setting offsets make your your decimals are correct take 2 minutes extra if not sure.
If you have experienced a CNC machine crash, you should not panic or rush to restart your machine. Instead, you should inspect the damage and assess the situation. You should turn off your machine and disconnect the power source, and then check your tool, workpiece, spindle, table, and other components for any cracks, dents, or deformations. You should also take pictures and notes of the damage, and report it to your supervisor or manager. You should not try to fix the damage yourself, unless you are qualified and authorized to do so.
Check for backlash in the ballscrew/thrust bearings. Too many crashes over time will require increased backlash compensation necessary to position correctly.
In addition to assessment of potential damages caused by a crash predictive maintenance plays a huge role ranging from water hardness degrading performance of an orifice on a water jet, high pressure lines to tool bits on a wood router dulling out and throwing material to diodes on a laser CNC being calibrated can all help mitigate costly crashes and minimal downtime on these dynamic and expensive pieces of equipment.
Once you have fixed the damage or replaced the parts, you can resume your program. However, you should not simply restart your program from the beginning, as this can cause more problems or crashes. Instead, you should use a restart method that allows you to skip the parts of your program that have already been completed, and resume from the point where the crash occurred. You can use methods like setting a new start line, using a block delete, or using a restart block. You should also recheck your code, offsets, feed, and speed before you resume your program.
Crashes can be caused by one of the previous tools. Review all the tools before restarting any program. Then proceed like a new program was started. Single block, distance to go screens, spindle load. The fixture itself could have sustained damage that can cause a new crash and it may not be apparent to the eye. Have quality layout the part when completed.
Invest in Vericut! Accurate tooling, machine models, and now Vericut can check the machine! It is the best way to prevent crashes and scrap parts.
We can implant the below practice as a part of safe operation practice for first time prove the program. "To check the *Distance To Go* " With the following steps. 0.Single block mode. 1.Keep the feed rate zero. 2.Press the cycle start button. 3.Now Check the distance to go on screen and Ensure that values showing in distance to go should be to as per the programmed axis. 3.Now you can open the feed nobe. Above practice always protects the machine , job and tool from crashing.
Crashes are almost always caused by incompetent programmers. Invest in skilled workers. It is far cheaper than repairing machines.
Simulations on Vericut, and try adding safety checks on your CAD/CAM GCODE pre machining. 4th generation of industry optimizes your GCODE auto S/F and stops just before hit on fixture or base.
In my experience Feed and rapid override dare your friends.