Tag Archives: laser

121: Anodized Aluminum Moai

When Jen and I were first researching buying a laser, we didn’t plan on buying the one we ended up with. We were looking to get a small, semi-portable solution. But my brother Johnny found a family out in Terre Haute, Indiana, who had owned their laser for about a year and realized they weren’t really using it as much as they’d like and they wanted to sell it. Buying the used laser meant I inherited some of the previous owner’s mistakes—like a damaged lens and rulers that had art engraved on them—but I had plenty of time to cover up those mistakes with my own.

One of the benefits of buying used is that the previous owner didn’t need their material stock anymore either. Bundled with the machine were dozens of small samples of various laser-ready materials, including a piece or two of black anodized aluminum. I dug up one of those old pieces while cleaning out the office, and realized that I hadn’t spent much time engraving on the medium, so I decided to give it a try!

I’ll probably never find out who these two are, but I’m sure they had fun engraving this picture!

This piece of anodized aluminum had a remnant from the previous owner: an engraving test of their own that they didn’t keep. It also had one corner clipped off, so maybe the leftover engraving I have was a test run and they kept a more successful engraving. Either way, the laser is way too low-power to actually cut through this metal, so I’d be limited to engraving the surface. I don’t have the tools necessary to cut this into a better shape, so our two buddies will, for the time being, remain a part of this experiment.

Full color, desaturated, and then inverted so that it would engrave properly.

I settled on a picture of the large moai head Jennifer took some years ago. This picture converted into black and white really well, and as you have to with all materials that engrave from dark to lighter colors, I had to invert the picture so that the laser would fire on white, not on black.

My first engraving test was too powerful: I typically use 35% power to lightly engrave surfaces, but the laser overpowered the black, creating a blown out image. I settled on 20% power—recommended in the laser driver’s settings for this medium—and the contrast was much better. That’s what I get for ignoring Universal’s built in material settings!

Because it only took one pass to get an acceptable result, I decided to use this project to compare a few of the settings available in the driver. When engraving art that has shades of grey, the machine has to dither to convert those to art it can engrave. The machinist can choose to have the laser convert those shades to a patterned halftone, use an error diffusion method, or use a threshold to convert the art to black and white. You can also select from seven different Image Density steps; the lowest step is the quickest and skips the most space on the material between horizontal lines, and the highest takes much longer and leaves very little space between each pass. The difference between those settings is pretty remarkable, but I didn’t want to do seven passes for each, so I decided upon odd numbered settings.

In the end, I made a matrix of engraving settings: each row is a different Dithering option, and each column is a different Image Density. Twelve engraving passes later, here is the result.

The full grid of engravings. Most of the difference in detail is lost in these photographs.

As expected, the image density settings took different amounts of time to finish. Density 1 took only 47 seconds to complete. Density 3 took 2:08, while the default density setting of 5 took 4:10. The maximum density setting took a whopping 15:13. Since the engraving speed isn’t really affected by the dithering option, the results were almost identical down the columns.

Lower density engravings make the dither pattern more obvious.

It’s clear in person (and less so in this photography) that error diffusion is the best option to get a good clean photograph engraved onto this medium. I’d be willing to bet that will be true for most materials, as the halftone pattern (while great for low color artwork) just doesn’t blend a photograph’s natural shades well. This is even true in the lower image density settings.

While the dither pattern all but disappears at image density 7, the time spent is too costly.

I think the default image density setting, 5, was well chosen. It’s an excellent middle ground between the time spent and the resulting image. You can’t really get a sense that the image is comprised of multiple horizontal lines like you can in setting 3, but you’re also not spending 15 minutes on a 2″ by 2.25″ photo.

119: Leather Twist Earrings Tutorial

Cutting leather was one of the first projects we did on the laser, way back in Week 3: Leather Cuffs.  While there really isn’t much new to say about the cutting and processing of the leather, I thought it would be fun to use some of the properties of leather (flexibility!) to make unique, laser cut earrings.  And, to make sure this post has something I’ve never done before, you’ll be getting a step by step tutorial!

Supplies Needed:

  • Leather, about 1mm thick or less.  One color, or 2 colors, whatever floats your boat.  (Pacific Leather has a great description of use by thickness of leather)
  • Leather cutting apparatus (we obviously used a laser, but Cricut machines can do it, and you could also use a simple blade or rotary cutter)
  • Ear wires
  • Jump rings (7mm or larger suggested, depending on your thickness of leather)
  • Two pairs of pliers, preferably smooth needle nose so you don’t damage the findings (ear wire and jump rings)

Step 1: Templates

Freehand paper template

For me, I actually had to make a hand cut paper version of this, just to understand the mechanics of it, and then transfer it to the computer.  I was having a little trouble envisioning the 3D-ness of the twist.  Luckily for you, I’ve done all the hard designing work for you, and you can print out this paper template.  Use it if you want to see how the mechanics of the twist works before cutting the real thing on your machine of choice, or as a guide if you are cutting by hand.

Get your earring template here!

This template is just for ONE earring.  If you want a pair, think about how you want the second earring to look.  If you’d like it to look the same, print out a second copy.  If you’d like your final earring to be mirrored (as I do), flip the template!

Step 2: Cut!

Cut your leather!  Refer back to Week 3: Leather Cuffs for specifics in laser cutting leather, and remember, it’s a sooty job.

Step 3: Twist!

What I did was make sure the holed lined up, and then gently wrapped the leather around each other. You can’t really twist like when you make paper twist – you still want the final product to lay flat.  So, a two dimensional twist, I guess.

Make sure you have two pieces where the zig zags are opposite each other
Lay one strip on top of the other.
Hold the base and gently start to wrap the pieces around each other.
Keep on twisting!
Fully twisted, holes neatly lined up on the ends.

Step 4: Fold in half!

I wanted to make the back look as nice as the front and create a little visual interest with a loop.  You can make your fold as sharp as you’d like it, or as sharp as the leather will let you.  Make sure the holes line up.

The length of twisted leather folded in half, so the ends, and all 4 holes, line up.

Step 5: Assemble!

Home made ear wire on the left, commercially made on the right, 7mm jump ring below.

Assembly can be  a touch tricky, as more commercially available ear wires have tiny loops, and will not accommodate 4 slices of leather.  I did try them on my homemade ear wires with a bigger loop, and while they did fit, they did not swing as well.  My final solution was to use a 7mm jump ring to thread through the holes on the ends of the leather strips.  This holds the dangle part together.

If you are new to jewelry making, here is a great Instructable on how to open jump rings properly.

Leather strung on the 7mm jump ring.  Ignore the fact I used a toothy pair of pliers.

To attach the ear wire and keep the earring’s orientation (aka – show the twist from the front not the loop) you have two options.  1 – put a second jump ring on to connect the ear wire to the jump ring you already have holding to leather together or 2 (my choice) – twist the loop on the ear wire so the hole is perpendicular to the hook.

Quick visual on how to twist the ear wire:

Hold the ear wire with two pairs of pliers. Make sure the pliers have a good grip on the whole loop, and the neck of the ear wire so you don’t distort the metal.
Twist the pliers in opposite directions so they are perpendicular
Wide loop is on the left, ear wire as manufactured on the right

Then open the loop like you did the jump ring and hook the jump ring on the dangle on.  Close the loop, enjoy your earring!

Step 6: Do it all again to make a pair!

How to make the alternate design on the right:

Alternate design – don’t twist! Just fold the stacked leather strips, continue on from there.
When the leather is not twisted, the strips don’t sit quite as nicely, and you can see by the bowing inside the loop. A dab of glue will fix affix it.

I hope you have fun trying this out!  You can also shake it up by only using the curvy strips, or the zig zag strips.  The design and tutorial is by Jennifer Putzier of Isette, copyright 2017, and is shared for personal use only, please!

117: PC Case Engraving

To ring in the new year, and celebrate the ten year anniversary of my previous build, I decided to build a new PC. Back in 2007, it was two years before we even started playing with lasers. This time around, I knew for sure I’d be laser engraving some piece or another. I’ve engraved a few macbooks and other portable devices, and I’ve even engraved a custom wood faceplate for a friend’s ATX midtower. So I’ve been pretty excited about the idea of engraving something on my own machine!

Over a few weeks in January I did the research, collected the parts, and then planned a small “build party” with some of my local PC enthusiast friends so we could put the machine together together. Hey, it only happens once a decade or so, that’s a pretty good excuse for a shindig, yeah?

From left to right, Brenn, Jen (<3), myself, Maul, Ray, and Mark. Also not pictured: Maul’s bro Joe! Thanks for the photography, Mark!

Together we had dinner, built the PC, played some couch games, and mulled over a few remaining questions. What should this new build be called? What part of the case will be laser engraved? What are we going to engrave on it? I was so wishy-washy on the name decision that I couldn’t even settle on it before the party was over. Furthermore, I wanted the engraving design to be related to the name, so I couldn’t really come to any decisions on that front, either. But we were able to figure out what part to engrave, and as it turned out, the answer was nothing.

Fractal Design’s Define C case is sexy, but made out of questionably engravable plastic.

The Fractal Design Define C is a sexy, sexy midtower ATX case. I love the shroud, I love the quiet, and I love the flat textured front. I like simple, unassuming case designs, and I wanted to continue down that road after my last build in an Antec P180B. But when we finally dug into the case, I learned a few laser-unfriendly things I could probably have sussed out from reviews online if I had been more thorough.

The front of the case is not an anodized aluminum plate, and it’s also not easily detached from the surrounding plastic chassis that covers the front exhaust system. It’s made out of the same plastic—it’s very pretty, with a subtle vertical brushed texture, but it’s still just the case plastic. Because the textured surface isn’t repeated anywhere on the inside (or indeed on any other external surface) I wasn’t going to be able to do an inconspicuous engraving test. So I wouldn’t be able to engrave the front plate, but what about the window?

On a quest for extreme sound dampening, my previous PC build didn’t have a window at all. But over the years I’ve kind of missed being able to peek in on my parts, so this time I bought a case with built-in acrylic window.

With a power shroud for modesty and excellent cable arrangement, who wouldn’t want to peek inside?

Unfortunately, there wasn’t going to be an easy way to test that material inconspicuously either, and with the  engraving quality difference between cast and extruded acrylics, I didn’t want to gamble.

When I looked closer at the acrylic window, I noticed there was a lip on the inside, one that would fit a secondary piece of acrylic just fine as long as the measurements were correct. So I did a couple of sizing tests with some old pieces of acrylic, got my measurements spot on, and settled on a solution: cut a separate piece of cast acrylic and snap it into the existing acrylic window. I wouldn’t technically be engraving the PC case after all, but the finished piece would still look as good. As a bonus, I’d be able to easily change out the acrylic in the future if I wanted to change the design.

Amusingly enough, it was mulling around design ideas that led me to my final decision on the name of the machine. I’ve always been a fan of the Metroid series, you can see it in some of my other projects. Most game servers I host have names based on “Maru Mari”, and you’ll be connecting to “Varia” if you try to stream content to my television. I had a feeling I’d end up going with the Metroid theme again, but it wasn’t until I thought about how much fun it would be to engrave the cold steel corridors of Tourian into acrylic that I really landed on it.

The full map is too big; I’d have to fit it in this cyan rectangle

Tourian is a big map. Well, it’s not big, but its hallways are long and the vertical shafts are all a daunting climb. I’d have to compress the map pretty significantly to make it fit the relatively tiny space I had for my acrylic window. To make matters worse, halfway through the design I realized I had laid out the template wrong and was designing for the measurements in landscape instead of portrait. But after cutting a few rooms in half (and completely excising the hallway before Mother Brain’s chamber) I was able to make it fit.

The final compressed map, corrected to a portrait aspect.

I added a few additional details (the opening text scroll and an excessively big title in the original typeface in the corner) and the design was finished. I cleaned up the acrylic, seated it in the window’s lip, and used a tiny bit of clear packing tape on the inside corners to make sure it wouldn’t somehow come loose.

A mockup of what the case might look like with the final design.

The panel looks great when it’s not connected to the computer, but as it turns out, I should look into buying some motherboard-powered LED strip lighting to brighten up this design. Most of the photography here is cleaned up to make the engraving visible, but it’s much more subtle than that when properly installed on the PC.

This door is all that’s left of a completely deleted room. Don’t tell the purists!

The end result may be disappointingly dim, but I still had a blast manipulating the Tourian map in a way that wouldn’t compromise the basic layout, and I will definitely be using what I’ve learned on this project to make some more “window inserts” for this case in the future. Once it’s lit up, the design itself should really shine, but for now it still makes for some pretty fun close up photography!

The engraving fights with the inner bits just a little more than I’d hoped.
I love that the escape shaft coincidentally has its own murky yellow and green lighting.
This example clearly shows how dim the engraving is compared to the LED-lit components inside.
A two character 8 segment LED readout hides in Tourian’s O.
One Metroid, permanently frozen.

109: Edge-Lit Acrylic

I’ve been playing a lot lately with a new toy I picked up from Inventables: a powered LED strip for edge lighting acrylic. It’s made in particular to work in tandem with specially made acrylics that transmit light efficiently, but I’ve found it works really well with simpler transparent and fluorescent acrylics.

The first dual-layer design.
The first dual-layer design.

My first test was with transparent orange material sourced at the Aurora Public Library’s Makerspace—check it out if you’re local!—and it seemed appropriate to design a little sign for the space as the test. Because the LED strip is designed to snap to the edge of a 1/4″ piece of acrylic and I only had 1/8″ material available, I decided to split the design across two layers of acrylic. The front layer included all of the vector engraving and the back layer was just the main title text filled. The resulting look is striking, but using two transparent layers means you have to be extra careful not to let any fingerprints or dust get in between.

The short sign lit up easily.
The short sign lit up easily. Please ignore the Macbook!

Around the same time, I was working with a local artist to create some wall décor based on the classic Pac-Man maze. We agreed pretty quickly that the lit effect would look great and settled on some fluorescent blue acrylic. The first several tests confirmed that the two layer effect would be excellent; dividing the pellets, ghosts and other objects from the maze walls might not be very visible in the photography, but it’s a really neat trick when you’re examining the piece up close.

A small cross-section of the Pac-Man design in two layers.
A small cross-section of the Pac-Man design in two layers.

One concern I continue to have is whether a single LED strip will be able to illuminate the entire flourescent blue acrylic sheet—this piece is 16 inches tall, towering compared to the 4″ makerspace sign. A quick test on some scrap acrylic shows that the light visibly dims near the top, but I won’t be able to know for sure how the final piece will look until a last-minute shipment of materials arrives. Speaking of that, here’s a pro tip: don’t assume you’ve got all the materials you need until the day you’re scheduled to cut! Always check, even if it’s something you always keep in stock, like the black cast acrylic that was supposed to be the backing layer for the finished Pac-Man piece.

A later single layer test cut with rounded vector engraved maze walls.
A later single layer test cut with rounded vector engraved maze walls.

Edge lit acrylic is a great look, and I’m might have to investigate the “EndLighten” brand or similar substrates to maximize light transmission. I know I’m also going to be looking into portable equivalents; this hardware has to plug into a wall. I’m sure that’ll be a post in the future; until then, look forward to an update on this post with additional pictures of the finished Pac-Man piece!

This crazy square panorama shows how the lighting falls off near the top. We'll see how it looks in the finished piece!
This crazy square panorama shows how the lighting falls off near the top. We’ll see how it looks in the finished piece!