What is wrong with these lightburn command lines

I am using a new LaserBoard (with the SD card installed) with this C02 laser:

When I connect the laser to the computer and turn it on, lightburn seems to recognize it… but that little progress bar stays at 100 percent, and it never stops saying “busy”… When I try to initiate a burn, nothing happens. Can anyone give me a tip on this?

Here is a photo of the command lines.

Because you did not mention setting the Device using GRBL you probably don’t have a correct device configuration. Have you verified that the OMTech firmware is compatible with LightBurn? If so, try this https://www.youtube.com/watch?v=jhGGeYxCcKw

Thanks a bunch for the tip! Unfortunalty, I went through those setup menus, and set the machine as a “new machine”, I selected GRBL, specified that it would be connected through USB, and homing in upper right, etc… and I’m getting the same message. Any other thoughts? I’m really hoping to get past this roadblock today. I am probably overlooking something simple. Thanks so very much for your help everyone!

Two questions:

1- Does OMTech setup tell you to use the GRBL firmware type?

2- What operating system are you using on the PC?

When I click “find my laser” in lightburn, omtech does not show up… I am not sure if I need to install a specific file on the flash-drive that came with this laser (it actually came with 2 of them)… So I’m not quite sure what OMtech setup needs to be done beyond what I’ve done… and the manual is super confusing (to me at least)…

Operating system is: Windows 10 Pro.

What direction to you think I should head in?

Thanks again!!

First off, I’m sorry for mentioning GRBL since this is C3D and it could have GRBL-LPC or it could have Smoothieware on it and there was no mention of what firmware is on the C3D board or even how you got it.

If you obtained the C3D from Cohesion it most likely has Smoothieware already installed and it came with a uSD card which has a file named config.txt.

Where did you get the C3D board that is in the machine?
Who installed the C3D into the machine and what instructions did they follow for installation?

I would’t expect LightBurn to show you OMTech as a choice because LightBurn communicates with the machine’s firmware so that is generally what you’d be looking for. But I see from that link the machine is not likely to come with the C3D.

Since you said you are running Windows, there are drivers for Windows USB system which I believe need to be installed. Did you install the C3D using these instructions and also follow the link on the bottom of this page for installing drivers for Windows? https://cohesion3d.com/knowledgebase/k40-with-m2nano-cohesion3d-laserboard-installation/

As far as what direction to take goes, we are still working on figuring out what you have, how it might be setup.

Doug, a little history on this. I’ve been helping Not setup the laser for his business. I recommended he swap out the stock controller for a Cohesion3D - which he has done, purchased from C3D. I’ve been on vacation so I recommend he post here. Note that the screenshot in the first post shows that Smoothieware is installed. I’m going to hop on a call with Nik now and once this is sorted we’ll post a follow-up here.

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sounds good and now see “smoothie” on the pic. Be aware that we don’t know for sure where that text is coming from and it could very well be LightBurn putting that there because the Smoothie firmware type was created for the Device. I say that because there seems to be problems communicating with the C3D board.

Ok, we recreated the printer configuration as Smothieware and the laser almost works properly. His home switches are in the upper left corner. Laaser homes correctly. X jog buttons jog in correct direction but the Y jog buttons jog in the opposite direction. I checked his config.txt and found:
beta_homing_direction home_to_max

and changed that to home_to_min Even after power cycling the C3D board the behavior is still the same. Other than this, he can cut, home, etc. but the Y jog direction is reversed AND the cut is also flipped in Y.

My smoothie-foo is weak (haven’t used it for years). I’m sure this is a simple config issue.

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Ok, so I changed the beta step direction like so:
beta_dir_pin 0.11! # Pin for beta stepper direction

Now the behavior is even odder. The jog buttons move in the correct directions, the cut is correct and not mirrored in Y but now, when the machine is homed, it homes to the X end stop (on the left) but it does not move in Y at all! Perplexing.

Changing back to remove ! and it homes correctly but mirrored moves in Y (so it is exactly as it was before, indicating that nothing odd is going on with wiring, etc).

EDIT, I am remote helping via video chat… When Nik homes with the beta dir inverted (0.11!) we are seeing the carriage move left to home X then it backs off X a bit and then we see a few mm move to the FRONT of the laser then stopping. The homing_order setting is commented out so it should home X and Y at the same time.

I wonder if it’s thinking the Y home switch is triggered so it stops?

I don’t get the X-min Y-max thing unless the home/origin position is set to left front…
My config, setup 4-5 years ago has x-min y-min and the home/origin is the left rear corner.

according to this and seeing other config.txt setup, the recommended setup is x-min and y-max endstop connections. this is the default config.txt setup for k40. In LightBurn the origin is setup as left front.

This is driving me sane!

So I read the Device Setup section and reconfigured the config.g back to stock. We set the origin to upper left. Now the laser attempts to home in front left - which is not correct.

Changing the beta dir pin back to 0.11! and the printer homes properly (back left) but the Y jog buttons and cuts are mirrored in Y.

I have 25 years of CNC, 3D printer and laser experience and even contributed to the smoothie open source project (the temperatureswitch module is my code) so this isn’t my first rodeo!

Here’s the details on his laser:

The X end stop is on the left, the Y end stop is at the back.

We can get homing to work but the cut and jog buttons are mirrored in Y. We can fix the cut and jog button so they aren’t mirrored but then it won’t home.

I should also add, we used M119 to test the end stop switches. Configured as stock config.g after homing M119 reports X min: 1, Y max: 1 and then jogging to the center of the bed, these read 0. This shows that wiring and switches are fine.

Then, if we change beta_homing_direction to home_to_min the laser homes but the Y min reads 1 both when homed and when the carriage is jogged to the center of the bed.

This is not making any sense to me at all!

Let me share my config.txt and then I will start looking at the settings to see what might be making things do oddness. Like what home_to_min does why it would not try to move to the endstop.

config-20180616-cohesion3D.txt (25.8 KB)

so it looks like you have to not only set the homing direction but also change the endstop pin. See this sections and look at my ‘beta’ settings. FYI, I don’t have a C3D so I don’t know if the pin numbers match the C3D. Hopefully the config.txt you have incuded pin number for both min and max endstop signals.

## Endstops
endstops_enable                              true             # the endstop module is enabled by default an
d can be disabled here
#corexy_homing                               false            # set to true if homing on a hbot or corexy
alpha_min_endstop                            1.24^            # add a ! to invert if endstop is NO connecte
d to ground
alpha_max_endstop                            nc #1.25^            # NOTE set to nc if this is not installed
alpha_homing_direction                       home_to_min      # or set to home_to_max and set alpha_max
alpha_min                                    0                # this gets loaded after homing when home_to_
min is set
alpha_max                                    200              # this gets loaded after homing when home_to_
max is set
beta_min_endstop                             1.26^            #
beta_max_endstop                             nc #1.27^            #
beta_homing_direction                        home_to_min      #
beta_min                                     0                #
beta_max                                     200              #
gamma_min_endstop                            nc #1.28^            #
gamma_max_endstop                            nc #1.29^            #
#gamma_homing_direction                       home_to_min      #
#gamma_min                                    0                #
#gamma_max                                    200              #

alpha_max_travel                             500              # max travel in mm for alpha/X axis when homi

Thanks, could it be the Y end stop wiring? I haven’t seen the board wired up but asked for photos.

you guys tested the x-min and y-max and it worked but when you changed to x-min y-min did you have him move the endstop to the different connector(y-min)? that would be why it didn’t move then. ie the floating endstop was probably defaulted to triggered so it was thinking there was no need to move.

No, didn’t move the y end stop connector. I suspect this is the issue. I’ll work with Nik on it. I asked him for a photo, that should tell what’s going on/

Michael, you guys almost had it working with the default config( endstop on x-min, y-max) except the Y axis was reversed in LightBurn and that tells me you probably had the Machine Device setting with the origin in the left rear instead of left front.

Origin and Home are different in the default C3D configuration. ie Home position is left rear where the switches are and the Origin is the left front.

You have to have both the firmware and the software on the computer/PC setup correctly. I setup Home and Origin as the same on my machine just so it was easier in my head, ie 0,0 was left rear. With Home L/R and Origin L/F then when you home the machine, your position is 0,max_y

does that make sense?