NEJE-like Laser as CNC upgrade

Phaedrux

@FelixH said in NEJE-like Laser as CNC upgrade:

M501 ; Load Stored Parameters M98 Pcustomconfig.g ; Execute custom config settings

What do you have in config-override.g and customconfig.g?

FelixH

@Phaedrux thanks a lot for your help. Actually shortly after I posted the question I found where the problem was. The command disabling the heated bed was being called twice. I cleaned it up and now everything seems to be working just fine. Thanks a lot again!

mdalacu

Hi.
I have successfully installed a NEJE 30W laser on my MPCNC powered by Duet 2 Wifi, FW version 3.2.2.
I have not used any additional boards or circuits other than the supplied test board.
The test board is ideal as you can put the laser in test mode with power 001 to focus it and than switch to TTL mode to run the job.
This is the pins that I have used:

In the configuration i have added this lines and commented out the one with M453:

;M950 H6 C"nil"
M452 C"exp.heater6" R255 S1 F20000

I hope that helps someone as i had to read hundreds of forum pages to get this far...

chimaeragh

@mdalacu Are there not any downsides with connecting this way? The laser wiki states you need a specific electronics to attach a laser to the Duet2. I'm thinking you may fry your Duet if 12v from your test board runs back into it.

mdalacu

@chimaeragh I really hope not. The test board underneath the display has an integrated circuit. I think it basically does the same thing as the circuit on the wiki. But I am not an electonist...by any means.
What can I tell you is that after almost 1h of total burning time, everything still works perfectly!

chimaeragh

@mdalacu I hope so. From the wiki... [Laser PWM Control( https://duet3d.dozuki.com/Wiki/Laser_PWM_control)

The circuit diagram for the needed circuit, including protection for shorting of 3v3 line to prevent unintended Laser Power on is shown below.

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I do not think the test board has a 74HCT02 Quad NOR Gate.

FelixH

@mdalacu I don't think they designed the circuit @chimaeragh displays just for the sake of it. I actually build that circuit with TTH components and it has been working great

mdalacu

@chimaeragh @FelixH Maybe someone with more knowledge than us could look at that test board and tell us if it is safe.
The test board has an IC roughly the same size as 74HCT02 underneath the 3 digit display, but I can not tell which one. I don't what to disassemble the board since it is working just great.

chimaeragh

@mdalacu Upon further investigation, I am certain the 74HCT02 Quad NOR Gate is required to prevent shorting of the 3v3 line and accidentally turning on the laser. I will advise you to get the board if you plan on doing much laser work. It cost me less than $42 to get a batch of 5 of these boards made, assembled and shipped to me at jlcpcb.com

FelixH

@mdalacu said in NEJE-like Laser as CNC upgrade:

@chimaeragh @FelixH Maybe someone with more knowledge than us could look at that test board and tell us if it is safe.
The test board has an IC roughly the same size as 74HCT02 underneath the 3 digit display, but I can not tell which one. I don't what to disassemble the board since it is working just great.

mmm... I do not need such information. As I said, I made myself the Duet recommended board for using lasers and it works as advertised...