Laser power adjustment/speed

A Former User

Perfect timing, just got a new low power uv laser to use with photosensitive pcbs - hope to test it asap

dc42

The laser power is adjusted every 5 milliseconds at present during acceleration and deceleration. I hope this is OK. In the longer term I will probably make the adjustment interval the greater of 3ms and 5 cycles at the laser PWM frequency.

clearlynotstef

Wow this post has been so helpful! I will be following the progress with lightburn integration closely, I'm so excited to hear that you're already working on it. RRF has the potential to be outstanding with laser as it is with filament!

Best,
Stefan

clearlynotstef

Do you have any idea of when Lightburn compatibility might come to fruition? I'm so happy to hear that you were working on it, but I can't get a sense of if its moving along or just something that was discussed and left alone.

Thanks,
Stefan

dc42

@clearlynotstef said in Laser power adjustment/speed:

Do you have any idea of when Lightburn compatibility might come to fruition? I'm so happy to hear that you were working on it, but I can't get a sense of if its moving along or just something that was discussed and left alone.

Thanks,
Stefan

LightBurn compatibility in what sense? I am fairly certain that firmware 2.03 and 3.0beta are already compatible with LightBurn. The difference is that 3.0beta implements velocity ramping.

TonyPagett

Do I need to activate this velocity ramping or does it just work as is when in laser mode?

dc42

@TonyPagett said in Laser power adjustment/speed:

Do I need to activate this velocity ramping or does it just work as is when in laser mode?

RRF3 implements velocity ramping when in laser mode, provided that you specify the laser power using S parameters on the G1 commands. So you don't need to enable it in Lightburn. RRF2 does not.

TonyPagett

@dc42 Thank you.
My next question is this. The following code moves the laser (CNC) in the defined square but only switches the laser on for the first line (or one side of the square).
M3 S255
G1 Y75.0000 Z0.01000 F2500.0
G1 X75.00000
G1 Y25.00000
G1 X25.00000
M03 S0

If I add an S command to each line it works OK

Is there a way round this?

dc42

Select "laser power sticky" in your M452 command. Preferably, don't use M3 to set the laser power, just use a S parameter on the first G1 move.

TonyPagett

Select "laser power sticky"

How do I do this?

dc42

https://duet3d.dozuki.com/Wiki/Gcode#Section_M452_Select_Laser_Printer_Mode

TonyPagett

@dc42 You put "Laser power sticky" in M42 .
That's what threw me

dc42

@TonyPagett said in Laser power adjustment/speed:

@dc42 You put "Laser power sticky" in M42 .
That's what threw me

Sorry about that!

TonyPagett

Not a problem
It would appear that I am on RRF2 as I am using a WorkBee from Ooznest so the velocity ramping is not useable