Introduction: DIY Laser Engraver With RGB
After browsing for some cheap Chinese laser engravers online, I stumbled upon some specimens that seemed to be made out of DVD readers. After digging deeper, I discovered that many makers had had the same idea before and had built their laser engravers out of reclaimed drives.
Because I also had some old DVD drives lying around, I decided to jump in the rabbit hole and make a remix of the DIY laser engraver project with a bonus touch: some RGB to make the whole thing extra custom (RGB wasn't dead yet at the time...).
This Instructable sums up more than a hundred hours of work put into a project that I'm very proud of.
Laser safety glasses
A Laser module (minimum 500mW to get some decent engravings)
CNC Shield V3
2 A4988 Drivers
Two old DVD drives
A RGB controller
Some MDF, screws, hot glue...
Step 1: Watch the Video
You can watch the video of the build here (if the video above does not work) : https://www.youtube.com/watch?v=T6KCUmaR7X4&t=19s
Step 2: The Design
I began by laying out the basic structure of the engraver on a drawing board.
The engraver needs two axis to be able to draw any image in 2D. These will be made out of the recycled rails from the DVD drives.
To maintain the rails in place, we need supports.
I decided to use thin particle board, with a layer of plexiglass sandwiched between them for the RGB lights to glow through.
On the front panel, we'll add all the buttons needed to control the machine: start/stop/resume/reset. We'll also mount the power switch for the laser and the master switch there, so they are easily accessible in case something goes wrong.
Step 3: The Side Pieces
I began by drawing a life scale template for the side support pieces. I then traced it on photoshop using a photo of the drawing as a reference. Unfortunately, I don't have the file anymore, but you can draw your own design by hand and photocopy it - it will make your engraver also unique in the world and it doesn't take very long.
MDF is really easy to work with, and I was able to cut all the pieces using only a hacksaw and cheap files (the plexiglass took me five days though...).
If you gave a scroll saw, it's time to get it out of the closet as it will save you a LOT of time if you decide to use the design I used. Or, you can make your life easier by skipping the holes.
Step 4: Salvaging the Rails From the DVD Drives
To get the rail out of the drives, there's no universal solution. Having dismantled quite a few of those, I can safely say that they are all different.
The safest bet is to remove all the screws you see to get rid of the top cover. Then, once you can't find any additional screws to remove, use a 9V battery to power the bay opening motor. That should reveal additional screws that also need to be removed.
Once you have taken care of every screw, you should have access to the rails that house the laser pickup along with a brushless motor and some other PCBs. Remove everything so you have just the rails, the motor and the plastic dolly that used to house the laser pickup.
Step 5: The X-axis
The support plate for the X-axis has to be made out of two layers of MDF, to adapt to the shape of the DVD driver rails. The two pieces can be glued together using basic wood glue, but before that, make sure you have sorted out where the cables to the motor are going to go through. I decided to hide mines completely by passing them through a hole that goes from the side to the location of the motor.
The DVD rails can then be screwed to the plate using the same three holes the rail was maintained in place in the DVD driver.
Step 6: Making Room for the RGB LEDs
The LEDs are going to be hidden inside the MDF pieces. Use a knife or a Dremel to dig the grooves for the LEDs as well as the cables to go through.
Also, make a channel for the X axis motor cables.
Step 7: Quick Tip: Use Old USB Cables to Get Thin Wire
The grooves we made aren't very wide. Thus, we can't use ordinary wire to wire up the LEDs.
The wire used in USB or Ethernet cords is really thin and perfect for our use!
Step 8: Paint and Wrap It!
To help diffuse the RGB light inside, I painted the MDF pieces white.
Then, to make the general appeal of the project cleaner, I wrapped all the outside sides in white fake carbon fiber vinyl wrap.
To avoid getting weird textures and bubbles on the wrapped sides, use some wood glue to seal the fibers in the MDF and make to the surface smoother.
Step 9: Reinforce the Structure
I was then able to screw the side supports and the X-axis plate together. The screws are going to be hidden once we add rest of the side support layers (but first, we'll have to take care of the RGB).
To get some decent engravings out of this machine, we have to make sure that the X and Y-axis are perfectly perpendicular. To reinforce the structure, I cut and fixed some tie plates to the sides of the engraver.
Step 10: The Y-axis
The Y-axis will be housed inside an old DVD driver enclosure.
First, remove all the stickers and drill the holes for the RGB lights and the X-axis motor cables. We'll also add RGB lights under the supports, in the enclosure, so the holes must be wide enough to also let some light pass through.
Cut a hole in the center of the enclosure that will later embed the Y-axis rails. I used a Dremel for this job.
To make the machine safer to use, glue some layers of MDF with hot glue to make a bottom for Y-axis bed.
For aesthetics, I painted the hole white and added some white
Step 11: The Y-axis Plate
The plate for the Y-axis was made out of an old floppy drive cover. Used some superglue along with a screw to fix it to the rails.
Step 12: The RGB Logo
Because I wanted to really make this engraver as custom as possible, I added my old logo on the side of the thing.
To illuminate the plexiglass panel, the best method is to mount the RGB strip on the side. That way, the light will fade gradually and the individual LED chips can't be seen.
Step 13: Finish the LEDs and Glue the Side Panels
To control the RGB, I used a cheap Chinese RGB controller. It's a lot easier and cheaper than to buy a second Arduino to take care of the lights.
I added some additional LEDs under the supports, in the enclosure.
Once I was sure that all the LEDs worked correctly, I glued the rest of the side panels together.
Step 14: Adding the Laser Heatsink
The laser module I'm using is 'only' 500mW, so it won't get very hot as the metal cylinder around the laser module already functions as a heatsink. However, in order to mount the laser securely to the X-axis, it's a good idea to use a cheap aluminum heatsink. It can be fixed to the X plate with some screws (to get it to the right distance from the rails, I added some additional layers of MDF).
And with this final step, the mechanical build of the engraver is finally complete! Time to tackle the electronics.
Step 15: The Electronics
Luckily, the Arduino shield we're using already has all the inputs and outputs labelled, so it's very easy to wire everything up. I also made a schematic to help you in the process.
The shield also has a built-in microstepping control - meaning that instead of using full steps or half steps like a large CNC would do, we can make the motors move by 1/16 or 1/32 of a step to make the laser move with the maximal precision possible. However, the motors will consume more electricity: they will get hot quicker.
To use the microstepping modes, short some of the mode pins together. Different combinations give different resolutions. Take a look at the chart for the different configurations possible.
When the shield is programmed, add the A4988 drivers to it and wire up the rest of the electronics.
To find the coils of the stepper motors, use a multimeter. If there's resistance between the two wires, you have a coil. On the schematic, the coils are represented by two wires of the same color.
Step 16: Flash the Arduino With GRBL
Step 17: The Software
To turn images into G-code, I used LaserGRBL. It can turn any JPEG or PNG image into a path in a matter of a few clicks using the contrast and brightness sliders. It's also possible to easily change the speed of the laser depending on the material that is going to be engraved.
To prevent the motors from spinning too much and damaging something, you can add the dimensions of the work surface to LaserGRBL, so it knows when to stop when moving the axes around manually in the control panel.
Now that you can finally spin the stepper motors, you may have to troubleshoot them:
- If your motors move in the wrong direction, change the order of the coil wires that are connected to the shield.
- If the motor is just very weak or makes weird noises, change the current that goes to the motors by turning the small silver trimmer on the A4988 driver.
- If your motor doesn't do anything, verify that you identified the coils correctly using the method described in step 15.
Step 18: Time to Engrave
Or as William Osman would say, it's LASER TIME!!!
This 500mW laser module can engrave dark plastics and leather very well. The amount of detail the motors can give is also insane (see the 3rd picture).
However, the laser can't engrave any wood. But for $25, I'm already very happy with it.
Step 19: Conclusion
I'm very happy that I did this project. When I started, I had no clue how I was going to make it work and in the end, it took me more time than I anticipated. But it was worth it! 😃
I learned a lot during the journey and the end result is truly unique.
Now that the machine is done, I haven't actually used it as much as I thought I would. The work surface is only around one square inch and the engravable object must be perfectly flat to get a constant burn from the laser beam.
If I had to make one of these again, I would probably skip the RGB, unless I have access to a real CNC engraver to help me cut the parts.
Now for the improvements:
.A more powerful laser would make this engraver more versatile. Right now, it can only engrave leather and plastics. Some wood marking capabilities would be welcome - or maybe even cutting? 🤔
.To make this engraver more secure to use, it would be wise to add an enclosure around it. As I said, I use it very rarely. If I upgrade the laser, I'll probably also add an enclosure.
Second Prize in the
CNC Contest 2020