Easily add a laser etcher to your CR-10 3D Printer

I recently stumbled across a useful laser etcher addon that I’ve wanted to add to one of my 3D printers for a while, but it’s been a little difficult to find something compatible and affordable. There also hasn’t been much in the way of documentation as to how to pull it all together. Hopefully, this post will pull all the details into one place to help others wanting to do the same.

A few notes to start though:

• this is an upgrade for the Creality CR-10 3D Printer. It’s a pretty generic laser module that runs off 12 volts but in this case, I’m attaching it to a CR-10. There isn’t any reason why it can’t work with lots of other printers, but I can’t help you figure out how to make it work with your [insert other printer name] machine
• this is a laser etcher – it cannot cut material. It can etch/engrave very soft things like wood, paper, cardboard, and the like. It’s simply not powerful enough to cut these items (although you may be able to cut some very thin items) – to cut you’d need a much more powerful laser, cooling & ventilation system plus a lot more safety mechanisms in place. It would also cost a LOT more than $50
• lasers (of any kind) are DANGEROUS – make sure you use proper eye protection (the module I bought included the necessary protective goggles) and don’t let your friends, kids, pets, etc near this thing when you’re operating it unless they have protection too. It’s also a good idea to have ventilation and fire suppression available when you’re using this device. Despite being a step up from a laser pointer, this module can still cause damage to you, your eyes or your home if you don’t treat it properly and carefully. Despite having safety glasses, I try to avoid spending too much time looking directly at the etching process…just to be safe. I also usually have my phone recording the process so I look at the screen instead of directly at the etching.

You’ll need this laser module. I bought mine on Amazon (disregard the bad reviews – it works fine…I suspect the lack of instructions in its use are the main reason for the reviews) but there are lots of places that sell something similar. I paid a little more to get it faster (via Prime) but you can likely find one similar at your favourite online shop. I bought a 500mw model but you can get them up to 2.5w if you want to pay more. I knew this would be just used to play with etching and I have access to more powerful laser cutters so I opted for this cheaper module…and honestly, the 500mw does the job just fine…it may just take longer to get the results of the higher powered modules.

The unit comes with the laser module itself (inside a heatsink with a fan on the top) with built in magnets that allow it to be attached to the metal extruder shroud on the CR-10 – obviously if you’ve swapped out that shroud, this likely won’t work for you but you should be able to rig something – even rubber bands would likely work.

A long wire comes out of the laser module that goes to a box with a 12V power connector. There should also be a separate wire with a white plastic connector to attach the power cable to the unpopulated fan port on the CR-10’s control board.

Inside the box I also got a set of green laser glasses and a small supply of wood sheets to use with the laser. There were no instructions provided.

Hardware Installation

You’ll need to power off the CR-10 and open up the control box. Turn it upside down and unscrew the cover. This video goes through the process if you want to see it before attempting it yourself.

Using the supplied cable, attach to the unused fan connector (see the yellow box in the image below for where on my CR-10 control board). There are a number of variants on this board – see this link to find your version. In my case, I have the original CR-10 board in black. If you don’t have an open port, you may need to make a splitter cable. This Reddit thread has more info and links.

The problem I found with my specific CR-10 is that I didn’t have anywhere to have the cable leave the control box so I ended up just using a pair of pliers and folding back a little bit of the sheet metal in the bottom ‘lid’ to allow the cable to come out the bottom. Once the bottom is screwed back on, the rubber feet provide enough clearance. I may replace this in the future with a printed bottom ‘lid’ with an additional fan which seems to be a common mod for the CR-10. But in this case, it worked fine for my purpose.

Next you’ll want to attach the laser itself to the extruder shroud. This assumes you have the original metal shroud still in place – this isn’t compatible with a Fang mod or any other hotend without some kind of modding. In my case, it just barely fit onto the left side of the shroud although the wire coming out of the laser module rubs against the gantry a little…I may disassemble it and rotate the cable to come straight out to the side.

You’ll want to route the cable from the laser module up and behind the gantry (follow the extruder wiring) as best you can – the wire could be a little longer to better reach the control box area and the power supply plugin.

In a perfect world, I’d be able to simply leave the laser mounted onto the shroud but I found when homing and regular operation, the cable got in the way or the module hit something. It’s probably better to remove it between laser sessions and keep the gantry lightweight for printing.

Software Workflow
There are a number of ways to create the required GCODE to run the laser and etch your text or images. I used Inkscape (a free and open source version of Illustrator) and a free plugin from J Tech Photonics. This plugin can be tricky to install but the link has all the details so I won’t go over them here.

The one downside to this plugin is that it only does outlines of your object and not fills. I’m still looking for other options that do fills properly (ideally opensource and Mac compatible) but I did come across a few that I’ve yet to try out: 3DPBurner Image to GCODE and Inkscape Laser which I hope to get to. J Tech also sells a few different applications that I may also try out.

Once everything was installed in Inkscape, I started by creating a new document that is the same size as the CR-10’s bed (300x300mm). This should give you a proper idea of the scale of the item you’ll be etching.

The J Tech link has very detailed instructions on preparing your image or text for etching but the TL:DR is that you need to have a vector graphic (ideally an SVG) or create something inside Inkscape (like text).

There are lots of ways of converting an image to an SVG but one of the best I’ve seen is PICSVG – a free, web tool for doing the conversion with a number of options you can preview in realtime before downloading the converted SVG which is ready to import into Inkscape.

Once you have imported your SVG or created your text, you’ll need to select it (by clicking on it) and then select “Object to Path” in the Path menu. Then navigate to the Extensions menu and choose “Generate Laser GCODE” and the J Tech plugin which will bring up a menu of options.

The next part will take some experimentation to get the settings right for your specific file, the material you’re etching onto and the quality you want. I used these settings after a bunch of experimentation:

The main ones you’ll want to change/experiment with are:

• Laser ON: by default this is set to M03 but Marlin uses M106 to turn on the fan port we’re using to control the laser module so set it to M106
• Laser OFF: Similarly, by default this is M05 but we want to use M107 to turn off the laser module
• Laser Power S#: 0 is off and 255 is full power. You can prolong the life of your laser by reducing this but you may have to go slower or do multiple passes
• Passes: how many times your etching code will run….multiple passes will make a darker image. I left this at 1 since you can also just run the GCODE again to darken it if you haven’t moved the material since it will home itself to the starting point.
• Laser speed: this is the speed the etching/burning process happens at. The slower the speed, the more time spend on a given spot and ultimately, the darker the burn/etch. You need to be careful with this setting though as if you slow it down too much, there is a chance it could burn too much. Speed it up too much and your etching will be faint or dull. Finding the sweet spot will take practice and patience.
• Directory: you’ll have to put in the full path to where you want to output your GCODE. There is no directory browser/picker

Note don’t check the “Live Preview” box.

Before I changed the defaults in the J Tech plugin, I was manually turning on/off the laser via the CR-10’s temperature sub menu (Control/Temperature/Fan Speed to 255) and was making some messy etchings since the laser was always on. Changing to the proper Marlin fan on/off meant a much cleaner etching.

When you click the “Apply” button, it will take some time to generate the GCODE file and will return back to the plugin menu when finished as well as draw a “0,0” and “100,0” text on your document to show you where the start is and where 100mm on the X is. Your object will also show the path moves.

You’re now ready to fire up the laser!

The other variable that can affect the amount of burn you get is the distance between the laser and the material (aka as the Z height on the printer). We don’t specify this when etching, just the X and Y movement.

The plugin will assume that 0,0 (x & y home) is the lower left of your Inkscape document. There isn’t any homing commands built into the output from the plugin, so you can manually move the home point (the motors will be disabled to allow this by default).

I typically set up the material and put some spoil material on top (or in place of) to run a few test etchings to make sure I’ve got things lined up correctly. If your test print shows that the laser isn’t focused, simply raise or lower the Z (manually, by adjusting the leadscrew). I’ve also got into the habit of adjusting my X & Y home by simply positioning the module on the X and the material on the Y by hand and turning on the printer with the module plugged in. This does fire the laser very briefly so ensure you’ve got your goggles on.

Usage
You’ll need to put the GCODE generated by the plugin onto the SD card and into the CR-10. Then, with the printer off, set up your material and manually position the X and Y axis to have the laser module at the lower left corner of your material. Now is a good time to put on your laser glasses (while everything is off).

I would typically start with the Z axis at about 100mm from the build surface but you’ll have to adjust depending on your material…so be prepared to make some mistakes on some test wood before you put that clean piece of wood (or whatever) in place.

Note to Octopi users: I wasn’t able to use this remotely via Octopi. I’m not sure if it was my setup/install or what but when I uploaded the gcode via the normal method I use with Octopi (dragging the file onto the website’s left side for a local upload or the right side for an SD card upload), it just didn’t work. You should probably be in front of the machine when doing this anyway to keep tabs on everything since this (laser etching) shouldn’t be done unattended and can easily start a fire. You can use Octopi to home X & Y (but NOT Z) but you’ll want to choose the GCODE file via the control knob on the CR-10 directly to start the etching process.

An example etching (on cedar plank) of too slow a laser speed so the detail got a little overcooked (left) and an example where I got the settings pretty good (right):

Here’s a timelapse of a converted image to SVG (this website’s logo):

and a real time video of the etching:

I haven’t had a chance to try a wider range of materials than the scrap wood I had along with the samples the laser came with. Keep in mind that some materials can really smell when being etched (wood smells great…like camping!) and some can even be dangerous depending on what chemicals where used in their creation so be careful, use ventilation and be ready to turn everything off quickly if you need to.

Check out this video for some fun experiments with different speeds and materials (including cutting paper and foam) as well as some other software options (including Fusion 360) for use with the laser module. It’s for the CR-8 machine but basically covers the same type of module addon:

Update (June 17, 2018): I found a MUCH better application for doing the etching. It’s called Lightburn and is a paid app (with a 100% functional 30 day free trial). It seems like a steal for $40 for what it does.

It supports just about every file type and image format you’d ever need to use with a laser and has all kind of great features. It’s also available as a native app for Windows, Mac and Linux so no more janky work arounds for me.

It has the ability to fill in any vector graphic you want to etch, not just outline like the tools mentioned above. You can import just about any image type and trace right in the app or simply burn a greyscale image:

I’m still dialling things in though…there is a lot more control with this app and I’m finding that I can reduce power and speed up the laser movements and still ‘overcook’ the project. But it’s so much nicer to use a tool that is native rather than plugins for Inkscape (don’t get me wrong, I love Inkscape – but it’s better at other things).

I also moved my laser to the front of the fan shroud…much less in the way and the wire is better orientated.