I've managed to get LaserWeb4 working with my Chinese Reje Laser running grbl 1.1f.

I’ve managed to get LaserWeb4 working with my Chinese Reje Laser running grbl 1.1f. Now that I can do a perfect raster job I want to tackle the problem that images come out mirrored. This is what I did:
home is bottom right, forward Y is along the long side (up), forward X is along the short side (left). I printed an SVG I made, basically a rectangle with tick marks at every cm along the X and Y axes.
When I run this in this configuration, I get nice lines and crisp tick marks, but the Y-axis to the right.

Studying the grbl documentation I found I should use $3=1 to revert the X-axis. So that’s what I did and I moved the home position to the bottom left and printed the SVG again from the same generated G-code, so nothing changed in between.

This time the rectangle comes at the correct position, with the Y-axis ticks on the left, but the lines are not as dark, sometimes parts are missing (although it’s a single line in the SVG) and most of the Y-axis tick marks are not visible.

Looks like an effect of the $3 setting, but what do I need to do to get the lines nice and clean AND the X-axis in the right direction?

@Helma_hepabolu , Hi, I got a Chinese laser (from lubandiy) based on arduino NANO 328p and I got also a mirror effect problem. Is it the same electronic board?

@Benjamin_BOIS Could very well be. Mine also has an arduino NANO 328p clone. I had to do some rewiring of the pins to get the laser mode of grlb 1.1 working. Did you have to do that too?

@Helma_hepabolu Yes, the same here. I have to use the pin D13 to get the laser variation working with grlb 1.1

check.
After some experimenting I found that the speed along the X-axis is way higher than the speed along the Y-axis. AND I need to bring the speed down to roughly 800 mm/min. Then, lines are continuous.
I also tightened the belt of the X-axis more, which gives cleaner (= straighter) lines.

So @Benjamin_BOIS I guess you also need to add $3=1 to you grbl settings.

@Helma_hepabolu I haven’t noticed a speed delta between axis X/Y. I’ll test ASAP the $3=1 into the settings, thx.

@Benjamin_BOIS In Grbl 1.1 laser PWM is on pin D11 (not D13). @Helma_hepabolu If your board was made for Grbl 0.8 you need to swap the PCB traces between pin D11 & D12.

+Peter van der Walt I understand the Cartesian system, but I find it difficult to translate it to a proper setup of my laser envrager. Right now, with the $3=1 setting, the home position is in the bottom left corner of the engraver, basically the same location it is on screen in LW4. I hope that’s the correct setup.

@cprezzi Thanks, did that some time ago and now it works fine.

+Peter van der Walt Great, that’s the way it’s setup now.
The only thing I now need to figure out, is how to move the laser back to the home position. I could do it in LaserWeb 3, but with LW4 it stays where it’s left after the last command. Other than using the jogging buttons I haven’t found a way to move it back to the home position. The ‘Goto XY Zero’ button also doesn’t seem to work.
Any ideas?

Ah great. Thanks!

Just checked: the goto zero button already has the correct codes. So it should have worked. I’ll check over the weekend.

I’m on 726, I’ll update first and report back