Having never done CAD/CAM (other than a fair amount of LASER cutting and enough 3D printing to make a Primo ) I am now faced with choosing and learning some software.
Where I’m Going:
My goal is for my MPCNC to be a LASER cutter. So since that is essentially a 2D system a traditional CAD package seems like overkill/more complex than I need. However, if it is the only option, then so be it.
Where I’ve Been:
I used a commercial LASER cutter for several years in my university lab before I retired. The workflow for that was super simple; Design in Adobe Illustrator, then “print” to the LASER cutter. The “print” driver would then let you select the material you were cutting or engraving, and automatically or manually you could set the LASER parameters. Any lines in the Illustrator file that were red and 0.072" in thickness were cuts. Anything else was engraving, proportional to the darkness of the image.
I know no such “print” driver exists for the MPCNC and never expected that - just explaining what I’ve had in the past.
Also, while I’ve used Windows over the years, I’m all Mac at home. And retired, so yeah, no PCs at all. So best case for me is a Mac workflow starting with Illustrator. If Windows is the only way, then I guess I’ll have to bite the bullet and get an inexpensive PC or install a virtualized Windows on my Mac.
The laser is a little less of a beaten path, but once you pass the crown, and have the laser controlled by pwm, it is the same as any marlin laser system, which is very similar to any grbl based laser system.
If you already have the skills and are paying for illustrator, use that for CAD. You just need some CAM.
Estlcam is what we recommend for milling. It is a windows program, but it is lightweight. I run it in wine in my ubuntu machine. Other mac users have decided to install windows in a vm to run it. But it isn’t great with lasers anyway.
Lightburn seems like a good choice, but I have only messed with the trial.
I know inkscape is sort of an open source alternative to illustrator, and there are some plugins for generating gcode from svgs in inkscape. I am sure you can find some info by searching for that.
Kiri:moto has a laser cutter component, but I haven’t used it, and I’m not sure it uses svgs.
This page doesn’t often get updated, but I wish the best information was on the software workflow page. Maybe that page needs an update? Or maybe we need a laser version of that?
Thank you @jeffeb3. If and when I get this figured out I’d be happy to write it up. (Heaven knows I did enough of that as a professor. ) And of course I’ll no doubt make a video as well. Just lots of moving parts at this point. I guess I’m Marlin with my SKR Pro? Some IT folks live to tinker with software/firmware/hardware… I outgrew that years ago. So I’ll leave the SKR the way it came for as long as I can.
It stands for “Pulse width modulation”, but that doesn’t really matter. The laser reads PWM and the skr pro is setting a pin to a specific PWM signal. In that way, the skr controls the lasers brightness through that pin. If you can control your laser with buttons on the screen, then your firmware and electronics are all set, and you just have to work on getting the gcode right.
PWM is a way of turning a pin high and low. The width of the on time, compared to the on + off time is what determines the intensity of the laser. If the signal is always on: full brightness. Always off: no brightness, 50%/50%: half brightness. But you don’t have to know that to use it.
Ah, thanks. I get that. Just didn’t recognize the abbreviation.
I have no actual LASER yet. Wanted to get the MPCNC working and the software sorted out before taking that next step 'cause getting and setting up a CO2 LASER is a whole 'nother level of fun.
I’ve used this Illustrator add-on before with my homebrew pen plotter. It works great, however it exports GRBL-compliant G-Code. You would probably need some sort of post-processor.
Maybe you can get it to work. It’s also very cheap and customizable.
Installed Lightburn. It found my MPCNC (But thought it was GRBL) via USB. I changed it to Marlin and set the proper work area. Won’t print via USB, but I drew a 10cm square and generated some gcode. I am happy to say that the results were a 10cm square. At the end Marlin threw an error:
On my K-40 I did a “brain transplant” with an Arduino/CNC-shield controller running grbl, a 2-channel accessory relay, and I run Lightburn software on a PC. I use the coolant gcode command to toggle air assist (just a regular $10 aquarium air pump) on/off. This was easy to set up in Lightburn - it’s been so long I don’t recall the steps off the top of my head, but it wasn’t hard to figure out. The trickiest part may be identifying the right pin to control the relay on your controller - the pin was labeled on my CNC shield so it was simple for me.
I considered using the other relay channel to toggle the cooling water pump, but was convinced by others that it made more sense just to run the water pump any time the machine was turned on. I suppose I could use the other relay to turn the LED lights on/off but for now those are hard-wired to the power supply as well.
I also got PWM control for laser intensity working pretty easily, but on my K-40 the laser was wired for inverted polarity on the PWM signal, so 5 volts is laser off, and 0 volts is full power. I found a schematic for a simple logic inverter using a transistor and it’s been working fine for years. Apparently there’s an alternate pin I could try on the K-40 power supply, but I’m hesitant to mess with a working configuration. My (apparently older) K-40 came with an analog ammeter and a potentiometer to control the current level. I left these in the circuit when adding the PWM control. I use the pot to set the max current, then use Lightburn to control from 0-100% within that limit. This way I don’t have to worry about the software inadvertently overdriving the laser tube.
I partitioned my Mac using boot camp and installed Windows, so I could use Vcarve. There is a free version of Windows within boot camp. So I can use either Windows or Mac, on the Mac, so far works great, been using it for a few months.
) I am now faced with choosing and learning some software.
) And of course I’ll no doubt make a video as well. Just lots of moving parts at this point. I guess I’m Marlin with my SKR Pro? Some IT folks live to tinker with software/firmware/hardware… I outgrew that years ago. 
, watching carefully.
