Laser safety problem

Hey there, new(ish) user here. This is just a concern of mine that I was looking for a solution to. I run a laser on my long mill (which is much easier to connect a laser to than a shapeoko 3 by the way) and when I hit the e-stop button for the controller the machine stops as it should but the laser continues to fire at whatever power setting it was at before the button was pressed. I have not tested this out much so it may be a dumb error on my part, but if it is not are there any suggestions for how to fix it? (If it is you can just tell me what my mistake was).

@cncenthusiast Welcome to the group.

Can you tell us more about your laser setup? If it is running off the pwm port on your Long Mill controller, the laser should be off when there is no movement. With more information, I’m sure that we can come up with something to help you out.

I am using a long mill 30 by 30. My laser is connected to the spinpwm port on the controller. My laser was a 10 watt real optical output system (I say was because it broke recently and I am waiting on a replacement). This actually is not a huge problem for me and I like the long mill overall but I think that it is strange that when you hit the e-stop your spindle/laser continues to fire.

@cncenthusiast I don’t know that laser, but is there a switch of any kind that toggles it between full power and pwm control? I know that on the Endurance, for example, that is the case. I’ve played with two generic Chinese lasers and an Endurance and none of them fired with the pwm wire connected and the Mill controller off. You are correct that this is an unsafe condition.

My laser does not have a switch. The only time that I had the problem with the e-stop was when I was running the laser during a job. When I hit the e-stop the cnc would stop moving but if the laser had been on when I hit the e-stop the laser would continue to fire.

by the way, do you like your Endurance?

I ordered a Endurance as a replacement for my old laser.

@cncenthusiast I don’t own the Endurance. I just get to play with it from time to time. It seems like a well made unit. I’ve watched some of his videos and he admits that his “10w” laser does not have a continuous output of 10w, so I guess that says something for him. I’m watching the development of the Sienci laser closely.

This has me wondering if mine does the same now. When I get home I’ll test it.

Some of the estop buttons have dual contacts, not sure if the button on the longmill does. If it does, I’d suggest taking your 12v power that goes to the laser and run it through the other contact set. Then when you hit the estop, it will kill power to the laser head.

The laser controller can be the part that fails also, so killing the PWM lead won’t help. Killing the main power would be best. In the end, the PWM is a software controlled pin on the board, not something to be used for safety in general.

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Hmm, “e-stop” means the button on the LM-controller or an external emergency stop?