I’m running a 5.5w blue laser. Connected to an SKR 1.4turbo 32 bit board on my 3d printer.
I’m trying to run a test card on some 1/8 plywood. It does the headers, the scale numbers for the chart, and then starts doing the burn circles – speed of 300 at 20%, 40%, 60%, 80% all looks file but as soon as it starts that last burn, it dies with ‘connection lost’. I thought it might be because of 100% power, so I tried 90%, still same result. I tried to output as gcode and run through Octoprint (which I’ve done before) and stops at the same spot. These are the last lines of my console before it dies:
G1 X78.67 Y89.76
G1 X78.06 Y89.99
G1 X77.48 Y90.27
G1 X76.93 Y90.6
G1 X76.42 Y90.98
G1 X75.95 Y91.41
G1 X75.52 Y91.89
G1 X75.13 Y92.4
G1 X74.8 Y92.95
G1 X74.52 Y93.53
G1 X74.3 Y94.14
G1 X74.13 Y94.78
G1 X74.03 Y95.44
G1 X74 Y96.12
G1 X74.03 Y96.8
M9
M106 S0 P1
G0 X91 Y96.12 F0
Layer C07
M106 P1 S229.5
G1 X91.03 Y96.8 F300
G1 X91.13 Y97.46
G1 X91.3 Y98.1
echo:Unknown command: “M9”
G1 X91.52 Y98.71
G1 X91.8 Y99.29
Connection lost
Stream completed in 12:14
There are a few of the M9 errors and I don’t have those commands turned on in Marlin (coolant control) and typically it ignores them - indeed it ignored every one before this.
I tried slowing down the baud rate to 115200 but it made no difference.
Make sure that it’s within all the bounds of your machine, and that the machine isn’t going to sleep, pulling too much power and browning out, or something along those lines.
One of the things I was thinking about was the power draw from the SKR board. My laser controller has the ability to accept external power so I disconnected the 12v to the SKR board and left only the PWM and ground, then set up 12v coming from the 600w PC power supply I use to power my 3D printer. Power is clean and stable and about to give it a try. Will post back soon.
Well, that’s not the problem. It definitely is not hitting boundaries - its in the middle of the 220x220 build area. I just removed all of the 100% components to at least see if the rest finish.
Ok, I don’t know what’s going on here. It went to the next line and stopped with “connection lost”. It should have been 20% power at speed of 600. Maybe I will try a different file.
I solved the problem by modifying the Marlin firmware. It was stopping on the air assist commands being sent, but that wasn’t obvious – only some it stopped on.
For those who need it, in Marlin:
in Configuration_adv.h line 3000 - uncomment #define COOLANT_CONTROL
line 3003 comment out #define COOLANT_FLOOD (assuming you don’t have it.
in your pins.h file (my case with an SKR - pins_BTT_SKR_V1_4.h) add #define COOLANT_MIST_PIN FAN0_PIN
I put it with my other definition that tells the firmware my laser is on FAN1_PIN.
I’m running a test image burn to white tile which failed immediately before these changes.