Z axis settings

[ppflores (Jose Flores)]

Hello,

I did modify my 7W laser engraver complete from the original Chinese laser engraver. U replaced the board for grbl 1.1 with control for 3 axis. Then I added the Z axis. I install limit switches for all X, Y and Z. So far so good everything works. When I home Z i do that in the upper part since I think is safer due I won’t damage my laser against the bed if something goes wrong.

My problem is:

When I home Z, the laser focal length, is too far from the surface of the material I want to cut/engrave. so I want to move Z down 40 mm (this will give me a focal length of 7.5 mm), to have it focus to the bed surface at that position, then I want to offset the material thickness so I can cut thicker materials. these are some of my setting in Light-burn. I have try pretty much all from the setting but not able to do so. Please any help will be much appreciated.

$0=10
$1=25
$2=0
$3=3
$4=0
$5=0
$6=0
$10=0
$11=0.010
$12=0.002
$13=0
$20=0
$21=0
$22=1
$23=7
$24=25.000
$25=500.000
$26=250
$27=1.000
$30=1000
$31=0
$32=1
$100=160.000
$101=160.000
$102=1600.000
$110=1000.000
$111=1000.000
$112=800.000
$120=30.000
$121=30.000
$122=30.000
$130=200.000
$131=200.000
$132=200.000

[LightBurn (Oz)]

Is your Z limit switch at the bottom of travel, or the top?

[ppflores (Jose Flores)]

I have both ends cover with limit switches the one on the top is covered due the install I did to hold the switch.

but home is in the upper position

you can see it in motion:

[ppflores (Jose Flores)]

So now I have more control. In this example I am engraving a circle, moving my Z 40mm down as I want, then I set the material thickness 5mm then to do 2 pases. Settings in photo one

on the second layer I also move Z 40mm down, just one pass but every time X, Y travels goes back to Z home position then goes back to 40mm after traveling. How can I stop moving Z back and forth every time travels?

here are the settings for layer 2:

and finally the video showing how it works:

[LightBurn (Oz)]

You can stop it from retracting constantly by enabling ‘Optimize Z moves’ in the device settings. It’s doing what it is to be safe.

[ppflores (Jose Flores)]

Tears of Joy rolling down my face. is working like I wanted to work.

Texas Stile Thanks,