With the new IR laser coming out, I figured testing and guides would follow. Lucky enough, it seems with minimal tweaks, Lightburn works with the new IR just fine. So here’s a guide on setting it up fully with Lightburn for auto-focusing and accurate results. Note; while I don’t have the 20/40W lasers, this guide SHOULD work for those as well. CONFIRMED WITH 40W I tested both USB connection, and using my Drag/Drop files
I - Gathering Information
You’ll need to find out homing placement, focus height, and cross laser offset.
1: Home the machine and take a picture of the screen. Save the Machine Coordinates.
(please ignore the control screen being for 3d printing, I did this before installing the firmware, but the data is fine)
2: Set the focus bar directly on the bed in the center and note the Z coordinate again
3: Subtract your focus Z height from homed Z height.
334 - 56.3 = 277.7 on my machine. Keep this handy.
4: IMPORTANT In settings > 2W Laser > Cross Line Indicator Offset, write down these values and then set them both to 0
II - Set Up Lightburn
1: This is mostly going to be in images, but start by creating a GRBL device with an X of 320 and Y of 350, front left, do not home on connect.
2: Device settings should look like this;
3: On the Gcode tab check to emit S-value and the header/footer.
4: You can start with my start/end and adjust as needed to zero in your own origin.
Start
M106 P0 S255
M1010 S3 P100
M1010 S4 P100
G28
G90
G54
G92 X-24.8 Y346.6 Z277.7
M3 S0
End
M5
G0 Z276.7 F6000
G28
5: You will mainly have to modify this line from the start; G92 X-24.8 Y346.6 Z277.7
Modify the Z277.7
to whatever you got from I - 3.
III - Finding Your Origin
1 - In lightburn, make a little 10x10 square and put it 20x20 out in the field.
2: Set it as a line engrave, and adjust speed/power appropriately depending on the material you’re using. I’m using an anodized aluminum card.
3: Make sure to set material height and absolute coords
IV - Run Your Test
1: Line up your material in the front left corner and secure it
2: Run the program and let it engrave.
(ignore the fact it’s off the front by about 0.5mm, I bumped it before taking the picture)
V - Calculate and Refine Results
1: Measure the distance from the left side to the square, and front to the square. It should be 20mm. If it’s different, take your result and subtract 20 from it.
2: Modify the start line G92 X-24.8 Y346.6 Z277.7
again. Take whatever your measurement results were and add/subtract to the X/Y values.
3: Adding to X moves Left, Subtracting from X moves Right.
5: Adding Y moves Down , Subtracting Y moves Up.
Sidenote; at least on my machine with the fast-homing, Y seems inconsistant and results can skew upwards to ~0.5mm (running the same file without change ontop of itself exposes the drift well). YMMV
6: Repeat Section V until dialed in to your own requirements.
VI - Enjoy Your Laser
1: Feel free to ask questions and comments
2: Experiment on your own and answer questions if you can
3: Share your results so everyone can see
I hope this guide is of use, and if anyone can test the guide with the 20/40W lasers and confirm it does work, please let me know!