Picture of Etched Acrylic Postcard #2: The Spiral Connection
This is my second attempt at sending out an acrylic postcard. I learned a few things the last time with the split-etched which surprised me by successfully reaching its destination. Instead of making a card that is cruel and tough to read I wanted to make one that could reveal itself all at once by closing one eye and getting the right angle and distance from the card.

So what did I learn?

Expand the bottom layer
In the original card, I cut up the image and put half on top and half on the bottom. I didn't take into account of how the thickness of the acrylic would make it impossible to see the images line up. It still looked cool so I mailed it, but I wanted a more complete look to it.

Use a visual cue
With 24 square inches of space to use, I was only using a small fraction of them. With an expanded bottom layer it would help to have a visual cue to let the user know where to hold the card to see the images line up. I started with circles, but spirals look cooler.

Use complementary images
With the visual cues of the spiral, I needed to make sure that I had two complementary images. This means that two shapes had to come together to form a solid mass.

So with all that in mind and the results right below this, this Instructable is meant to show how the layers were created in Illustrator. Several other imaging programs can be used as well. I am just using what I'm used to.

Materials and Tools
Scrap 3/8" acrylic from Tap Plastics.
Laser cutting and etching with Squid Labs' Epilog Mini 24.
Vector illustration with Adobe Illustrator CS.

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Step 1: Make a Spiral

Picture of Make a Spiral
Easy enough. Just click on the spiral icon, the one hiding behind the line icon, and click on the screen to bring up this window.

I punched in:
Radius = 4 in.
Decay = 90%
Segments = 100

Step 2: Copy It

Picture of Copy It
Alt-click-drag and wha-hey! A new spiral appears.

Step 3: Give it a Half Rotation

Picture of Give it a Half Rotation
Transform the new spiral with a 180-degree rotation to flip it.
cornec6 years ago
Doesn't it smell really bad??
cowe cornec5 years ago
depends on the type of acrylic - extruded acrylic (which is mostly used for its ability to get a smoother, more flame-finished laser cut) smells like DEATH, imho. do not want. ...while cast acrylic (which, though more expensive, is always my preference, as you can get a more refined/even looking raster engraving, and still a decent looking cut) has a sweet smell when lasered, similar to the candy-like bouquet wafting through a nail salon. always good to have a nice filtration setup though, so you're not stuck in an acrylic fume-cloud all day.
Booyaka35 years ago
Awesome Instructable, now all I need is to convince my dad I need a Laser Cutter well Good Luck to me!!
Xenel6 years ago
Step 11, Optical Illusion Alert!
cornec6 years ago
I understand etching is much slower then the cutting setting. And how long does it take to etch per block?
idontcare7 years ago
you could also combine it with the IKEA Window Postcard
Tofu7 years ago
I'm just curious as to how the piece handled the shipping rigors. Did it get chipped up, scratched, cracked? It looks great in the photos but I'd be curious to see how it looked when it arrived at the destination. Finally, you should start a cottage biz making desk placards like this. I would sooooooo pay for one of these.
fungus amungus (author)  Tofu7 years ago
They all came out in near pristine condition. It was really odd. If I had my own laser cutter, I'd likely make more stuff to sell, but as it is I just use the one at Squid Labs when I can.
robonut6258 years ago
Very nice! I really like that clean look!
nah8 years ago
That's great. It also makes me wonder how it would look if it were colored. Maybe make the top spiral red and the bottom white, or whatever colors you like. I'm not really sure how this could be done, because etching wouldn't work. Does anyone know of a translucent dye that might do the job?
Hey, it's very cool. But I'm reminded of the old Steve Martin joke: "How you can make a million dollars and never pay taxes! First, get a million dollars...."
What do you have to do to laser cut acyrlic? And how do you etch it? If you want to be really helpful, you gotta turn loose of more information. Otherwise, you're just showing off. (A cool thing to show off, mind you, but still just showing off.)
Etching acrylic, can you not just buy some etching spray? In the UK it's sold in DIY stores, make a template out of card, after all most modern printers are accurate to 5760x1440dpi or more. Then use that as a mask? Just because you don't have all of the fancy kit, doesn't mean you can't do it a slightly more labour intensive manner. Not to say that I wouldn't mind a free Laser cutter.
fungus amungus (author)  pinski18 years ago
Isn't etching spray for glass? I've read that if you dilute acetone in methanol you can frost it, but neither one will work for a design with so many tiny curves as this one. I'd suggest finding a way to transfer the images onto the acrylic. That way you can even use color.
fungus amungus (author)  L.L.Moorloch8 years ago
I disagree about just showing off. The goal is to explore how to create two layers that can come together when looking at it in the right way. Would I take the time to post 15 steps to show you how to create the layers from scratch if I was just showing off? No, I'd just post a photo and be done with it. Am I showing off that I have a copy of Illustrator as well? Not to point out the obvious or anything, but to laser cut acrylic you'll need a laser cutter. They run about $15,000 and I'm fortunate enough to get time on one and I know that's rare. If you have access to one of those, then the rest is obvious. I've touched upon the subject many times before and didn't feel like repeating it again. I should copy and paste some previous text and put that in here. If you don't have a laser cutter you can take the same ideas and print the results onto transparencies and then glue them to a piece of acrylic you can cut with some cheap and accessible tools.
ursonate8 years ago
So how did you stick the postage on?
fungus amungus (author)  ursonate8 years ago
Sticky side down.
That is incredible. I simply don't have to words to express what an awesome project this is. You have some lucky friends.
fungus amungus (author)  Brian Henderson8 years ago
Thanks. They have all my best stuff. The only pieces I still have are the mess-ups and prototypes.
steffrock8 years ago
i'm new here, so i have a basic question...the illustrator stuff i get, but buying the acrylic piece(where?) and laser cutting(how, with what?) is the stuff I don't get. plus, was there limitations or issues with posting it as a "postcard?" thanks, newb ps. i'll try to look at your previous job and maybe that'll answer me questionns.
fungus amungus (author)  steffrock8 years ago
Added info on materials and tools to Intro. Technically, it's not a postcard since it's not printed on card stock. The definition I've been given at post offices is a letter or even a large letter or maybe a flat package. It varies, but I always pay whatever's necessary to get it through.