Weekend Builds: Laser Cutting and Engraving
When it comes to digital fabrication, MatterHackers is your one-stop-shop for all your equipment and material needs, like laser cutters and engravers. While we carry several different machines, this article is going to focus on the FSL Muse and the companion software, Retina Engrave 3, simply because I’m most familiar with that laser cutter and its workflow.
There’s a lot of different things you can actually do with your laser cutter once you have it, more than I could even think of. To give you an idea of what you can do, I’m going to work on three different projects around three different concepts: reconstructing a 3D model, engraving a pattern, and creating custom packaging. Let’s get to it!
Laser Cutting a 3D Model
Autodesk has a really handy program that will take an imported 3D model and slice it into layers that can then be sent to your laser cutter or cut out by hand: Autodesk Slicer for Fusion360. While this slicer works very similarly to a slicer for a 3D printer, it’s features and functionality are tailor made for laser cutting.
You start off by importing your 3D model, which will pop in a bunch of new settings like how big do you want your finished object with a preview of it on the right side. The first thing you will want to do is select your “Manufacturing Settings” which is the size of your material in X, Y, and Z. You can either pick from a drop down of material options, or you can create your own material. You need to be very specific on the thickness of your material, otherwise a sphere may look more like an egg by the time you’re finished.
Once you’ve got your object and material settings right, you can choose your construction technique.
- Stacked slices works almost exactly like 3D printing; it cuts your object into layers that can then be glued together to recreate your shape. The “resolution” of your finish object is limited by your material thickness in the same way. This will be the method I focus on today.
- Interlocked slices cuts your 3D model in two perpendicular planes, then adds slots to the silhouettes. All the pieces will slot together to form your object, however some models may not work in this method, due to either overlapping slots with oddly shaped models or even parts that end up too small the slot into anything.
- Curve is like interlocked slices, except the second set of pieces are at an angle instead of parallel with an axis.
- Radial has interlocking slices start from a central point on the 3D model.
- Folded Panels takes the polygons of your 3D model and flattens it out so you can print it out and fold it back together to create your object. This really only works for models with a lower poly count rather than anything with high detail.
- 3D Slices seems to be a way to slice you model into layers without changing or estimating its geometry, but you can’t actually use or export this.
Stacked slices will bring the most detail out of your 3D model, at the cost of more material and time, but the end result will look that much better! You can choose to add dowels through your model for rigidity, but in my case this deer head doesn’t have enough space for a dowel to do much good. I can also change the slice direction to get more detail, just like rotating a model for 3D printing to prioritize detail. Once I’m happy, I will click “Get Plans” to be prompted to export the cutouts in sheets as DXF, EPS, or PDF. DXF is going to be the best choice for laser cutting in my case, but your laser cutter’s software may prefer a different file format. In that case you can use an online converter to get to the right file type. Make sure to save this project so you know how to assemble it later; there will be a lot of pieces!
Now that I have the plans for it, I can import these into RE3. Once it’s been processed I can remove the full image layer (which could be used to raster/engrave this onto my material) and make sure my sizing is correct, because sometimes that can get lost moving from one software to another. You will want to do some test cuts first on some scrap material to see the combination of power, speed, and current you’ll need to cut through your material. For the FSL Muse, I used 25% power, 100% speed, and 100% current for 3/16” cardboard and that worked really well.
As more and more pieces were cut out, the immense puzzle began to come together. Checking back and forth between the assembly steps and what I had cut out, I was able to put together subassemblies as it progressed, until finally the last sheet was done and I could hot glue and super glue the last few pieces together.
Engraving an Image
This is one of the simplest project you can do on a laser engraver. The only prep work that’s needed is to measure out the material you’re going to use and come up with a plan of what you want to engrave onto it.
From there, you can either jump into your favorite image editing software, utilize the tools within the laser cutter software (basic tools like text and shapes) or import a photo to convert and engrave within the software. Dylan threw together a quick design to commemorate our Community Hex Wall which I could then import into Retina Engrave 3 and tune my engrave settings. I’m going to be engraving on a piece of Cherry MatterHackers Project Wood and with a nice piece of wood like this, I don’t want to be too aggressive it, for fear that it will burn too strongly. Instead, with something like this where you don’t have a chance to do some tests, it’s better to start with a lower power setting and do multiple passes.
For this plaque, we ended up doing two passes at 50% power and 100% speed, and that gave it a nice contrasting color with some good depth to it. Engraving took only a half hour, including the time to design it, prep the laser cutter, and prep the settings needed for the design. If this were something you wanted to do batches of, it would be even quicker to accomplish once you have the technique down to a science.
Custom Foam Packaging
I’ve had a little tool case for over a year now that I wanted the perfect use for, and with the Nintendo Switch being such a fun and popular item right now with Super Smash battles at least once a week in the office, it made sense to make it a case for a Switch controller.
Venegade on Thingiverse designed a really cool grip for the Joycons that I have printed and would make designing a case really easy. All I had to do was import some Switch controller stand-ins and line them up in the controller case, color the models black to make it easier to trace, then take a screenshot from a front facing view. From there I could pass it off to Dylan to create an SVG, or vector, file using Adobe Illustrator.
Just the same as all the rest, I could import this SVG file into RE3 and set the laser power for the packing foam in it, and just like the Project Wood, I only had one piece to use for testing and final version. To play it safe, I set the laser power to 15%, speed to 100%, and current to 100%, and surprisingly it cut through the foam like butter after the first pass. A couple dabs of super glue and now I have a custom case the securely protects my Switch Joycons for gaming on the go.
Whether you’re looking to create your next hit product or just something fun to put together, each of these projects should hopefully get some gears turning and encourage you to try it out. Share with me on Twitter what you've created, I'd love to see it!