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CNC Training Module: Section 2.7: Fast Start - Crash & Recovery

Lesson 3: Stop & Three Step Recovery

This tutorial provides a detailed guide on how to stop a CNC machine safely and effectively, covering different stopping methods and recovery processes. The instructor explains the importance of understanding both hard and soft stops, as well as the necessary steps to recover from various stopping scenarios. Key points discussed include:

  1. Introduction to stopping the machine and its significance
  2. Explanation of hard stop: emergency stop and reset button
    • Hard stop to halt the machine immediately
    • Using the emergency stop switch
    • Reset button as an alternative hard stop
  3. Discussion of soft stop: using the pause button during a program
    • How to pause and resume a program
    • Differences between pause and stop functions
  4. Overview of the three-step recovery process after stopping the machine
    • Step 1: Using the reset button for quick recovery
    • Step 2: Homing the system if stuck
    • Step 3: Powering off and on for full reset in special cases

Main purpose: To teach users the essential techniques for stopping a CNC machine safely, including hard and soft stops, and to outline recovery procedures for various scenarios.

Key takeaways:

  • Understanding the difference between hard and soft stops
  • Effective use of emergency stop and reset buttons
  • How to pause and resume operations safely during programming
  • Three-step process for recovering from machine stops
  • Importance of powering off and on in specific situations for full system reset

Video Summary

Remember This Checklist:

  1. Understand the difference between hard stop and soft stop
  2. Learn how to use the emergency stop switch
  3. Master the use of the pause button for controlled stops
  4. Implement the three-step recovery process for machine resets
  5. Know when to power off and power on the machine

Introduction to Stopping the Machine (0:00-1:30)

0:00-0:05 – Introduction to the training video
0:05-0:14 – Overview of different stopping methods for the machine
0:14-0:30 – Explanation of hard stop vs. soft stop and their purposes
0:30-0:50 – Details on the emergency stop switch location and function
0:50-1:30 – Demonstration of stopping the machine during a sequence with the emergency stop

Hard Stop Techniques (1:30-3:00)

1:30-1:45 – Description of using the emergency stop switch to halt machine motion
1:45-2:10 – Explanation of releasing the emergency stop and returning to operation
2:10-2:30 – Alternative method: using the reset button for a hard stop
2:30-3:00 – Demonstration of the reset button as a quick stop method during a sequence

Soft Stop Methods (3:00-4:30)

3:00-3:20 – Introduction to soft stop and its application during program execution
3:20-3:45 – Demonstration of using the pause button to stop the machine without halting the spindle
3:45-4:10 – Explanation of options after a soft stop: resume or stop the program
4:10-4:30 – Summary of how soft and hard stops differ in practice

Recovery Process After Stopping (4:30-6:10)

4:30-4:50 – Introduction to the three-step recovery process after a stop
4:50-5:10 – Step 1: Using the reset button to clear most stop situations
5:10-5:30 – Step 2: Homing the system if it remains stuck after a stop
5:30-6:10 – Step 3: Powering off and on for full system resets in specific situations

Conclusion and Final Instructions (6:10-6:28)

6:10-6:20 – Recap of when to perform a power cycle for recovery
6:20-6:28 – Final thoughts and encouragement to practice the techniques discussed

Full Video Transcript

Introduction to Stopping the Machine (0:00-1:30)

0:00-1:32: “Hey, hey, welcome back to another training video. Today we’re gonna be going over how to stop the machine in a couple of different ways, but also how to recover from different stopping situations. There’s three steps that will be involved and we’re gonna make sure that you understand how to recover from stopping the machine, either from the middle of a program or a tool change, or even a setup procedure. There are really two methods of stopping the machine. One is a hard stop and one is a soft stop. The hard stop, also known as an emergency stop, uh, makes it so that we can stop the machine as soon as possible either to prevent something from happening or if it’s already in the middle of doing something wrong, we need to stop it. Um, immediately the emergency stop switch is located right here on the controller. It’s just a physical button that you press in. Um, that will then stop the machine, all axes and even the spindle will turn off and then you’ll need to release it. Just follow the instructions on the button. And this one I need to rotate clockwise. It will release, and now I can continue to move and do whatever procedures I wish to do to set up and run parts. So for this demonstration, we’re going to stop the machine in the middle of a sequence. In this process, um, we would normally be doing a smart tool touch off where the cutter would be touching off a smart tool pad to set up our Z zero procedure. But let’s say in this example, I forgot to put my pad under my cutter and I started my smart tool sequence.”

Hard Stop Techniques (1:30-3:00)

1:29-3:00: “under my cutter and I started my smart tool sequence. So if we go here, let’s say to the horizontal table, over to our smart tool display screen, and I click multiple tools, it will start plunging down regardless if there’s a pad underneath of that. So I can now hit the emergency stop switch and you can see that stops the motion of our process and it activated the reset button and we can deactivate the EWI by simply rotating it and it will deactivate the reset button and we can then continue on doing whatever procedures we want to do. Another method of stopping the machine immediately as a hard stop, um, is also simply pressing the reset button. And so for example, if we just repeat that process, the multi-tool, it starts plunging down without anything underneath, I can just press the reset and that will stop it as well. It’s the same sequence as pushing the E-stop button. It’s just, uh, faster and more intuitive to press the e-stop button because it’s a physical button versus a digital one. Now, the next type of stop that we mentioned previously is a soft stop, and this is used specifically when running a program. So here I’ve loaded a a simple just surfacing routine. And so if we push play here and just let it run through, um, we should be able to use the other controls next to the play button, such as pause as the soft stop and that will temporarily pause it”

Soft Stop Methods (3:00-4:30)

2:58-3:08: “and that will temporarily pause it and then from that pause we can either push play or stop and I’ll show you both options, um, throughout this demonstration. So let’s push play.”

3:22-3:41: “So in the middle of the program we can push the pause button and that stops all motion of the x, y, and Z axis. However, the spindle is still rotating from here. It’s a controlled stop and we can either push play to continue on from the pause or we can push stop to stop the program here. If we push play, it just continues on with the program.”

3:47-3:53: “Now if we pause again, let’s see what happens when we push stop, it lifts up the cutter and then turns off the spindle.”

3:57-4:29: “So those are some examples of a hard stop using the emergency stop switch as well as the reset button as well as a controlled soft stop when we’re in the middle of a program using the pause button. And we can either decide to again, push play to continue or stop to stop the program. Uh, one last thing I want to cover in the video is what I call the three step recovery process. Anytime you stop the machine, these are the three steps that we use to get the system back on track and they are reset home system”

Recovery Process After Stopping (4:30-6:10)

4:30-6:11: “and power off and power on. Now you don’t have to actually perform all three of those tasks to reset the system. I’m gonna go through each one, um, and just make sure you understand the procedures on how to do each one in order to get your system back on track. So the first step in recovery is simply using the reset button. So it doesn’t matter if I’ve paused it and stopped it or used the emergency emergency stop switch by simply pressing the reset button here, um, that does a first level of clearance and we should be able to carry on using that simple procedure a majority of the time. Now the second process will require you to home your system if by chance, if the machine is still stuck in a stopped mode. To do that, we’re gonna have to go to the home screen and we can push the home system at any time. It will just take from this location a long time to get it back to that homing location for this four byte maverick. So I’m actually gonna park the system first and then we can home the system. And this goes another level deeper, making sure it’s resetting certain parameters and settings for the machine. Now those first two procedures of using the reset button and homing the system will usually take care of 99% of most stops that you’re going to run into with the system itself. However, there are two situations that do require you to power off and power on the machine to do a full system reset. And that is if you stop the machine in the middle”

Conclusion and Final Instructions (6:10-6:28)

6:09-6:28: “And that is if you stop the machine in the middle of a smart tool, touch off sequence, um, or if it’s in the middle of a tool change sequence, whether if it’s manual tool change or auto tool change, if you actually stop the machine in the middle of that sequence, um, we’ll need to do a full power off and power on to get it back on track.”