Introduction: Split-Etched Acrylic Postcard - Optical Trickery

Picture of Split-Etched Acrylic Postcard - Optical Trickery

If the postal workers don't hate me now, this laser-etched piece might turn them to the dark side. If I'm lucky they'll have a fondness for optical tricks and get this postcard to the right place.

On this thick piece of acrylic I sliced up the addresses into two images and etched each one on opposite sides. the only way to look at the thing and make any sense of it is to close one eye and carefully move it around to change the angle.

With no changes to the bottom image in terms of distortion or size it's impossible to line up the front and back to make the whole address "pop" into view. You can't even get a whole zip code to line up just right. And yet it's still readable if you put just a tiny bit of time into it. So it should make it through. I even put Priority Mail postage on this one for an extra boost through the system.

Step 1: Make the Postcard Design

Picture of Make the Postcard Design

For all the steps here, I used Illustrator CS2, but this is very simple stuffe and can be asily done in other graphics programs.

This card is a little bigger than normal at 7x5, but the rounded corners will make it a bit friendlier. Don't want anyone to poke themselves with this thing, right?

Now just plop in the addresses. Good old Flibberty and Howard get to resume their communication in this example. Thanks, guys!

Step 2: Create a Slice

Picture of Create a Slice

I figured that a .05-inch slice would be great. No reason, really, it was just a guess. I thought that would truly be pushing it, but after seeing the results I could probably have gone to .02-inch slices.

Creating a slice is as simple as creating a new rectangle. Make it wide enough to vey comfortably fit each of the addresses and set the height to .05. Keep the fill color black for now as it will make the next few steps a lot easier.

Step 3: From One to Many

Picture of From One to Many

Select the slice and make a copy of it by alt-clicking (other software/OS X will vary) and dragging it down. With luck or guides you'll have the new slice right below the first.

That go over just fine? Great! Now select the whole bunch and repeat until the pile is bigger than both addresses combined.

Step 4: Cut Out Every Other Slice

Picture of Cut Out Every Other Slice

Go through the pile of slices and cut out every other one. Click and delete until you get this lovely pattern.

You could also incorporate this step into the previous one to save some time. I'll do that next time when I create smaller slices. For now this didn't take too long. Less time than writing this paragraph, that's for sure.

Step 5: Copy and Slide Down

Picture of Copy and Slide Down

Now select the whole group and copy and slide it over to the side, either direction is fine. Once the new group is right next to the original one, drop it down the height of one slice.

You should now have two patterns that are offset by .05 inch.

Step 6: Get the Addresses Ready

Picture of Get the Addresses Ready

Copy the addresses below the pattern. Now copy them again, lfip them, and shift them over to the right WITHOUT moving them up or down. In Adobe programs this is done by holding the Shift button. Messing up this step will ruin the whole effect. But relax, it's easy.

Step 7: Bleach the Sucker

Picture of Bleach the Sucker

Select the group of slices and change the fill color to white.

If you haven't done so already, separate the different groups into individual layers with the slices layer on top.

Step 8: The Cover-Up

Picture of The Cover-Up

Drop the slices down over the addresses.

Step 9: Sliced Up

Picture of Sliced Up

Now de-select the slices and you have your new addresses to be etched onto the acrylic. The left pair goes on the top and the right pair goes on the bottom.

Step 10: Etch and Cut

Picture of Etch and Cut

Getting the alignment right for the addresses is tricky since a shift of a few millimeters will ruin it. After a couple of tries I was able to get a card with the etched pieces close enough to complete the effect. It's still not perfect so I'll try it again.

So my advice for anyone who would actually go though with this is... good luck! Results will vary with different machines and enjoy some trial and error. I would have made more, but I only had so much acrylic to work with. That's what I get for buying the cheap scraps at Tap Plastics.

Step 11: Success!

It took a week even with the Priority Mail postage, but the card made it. Of all the things I've sent, this one surprised me the most. But it's out there in Georgia with my friends who occasionally break out their digital camera.

So no pics yet, but someday soon I will convince them.


wuggums47 (author)2008-07-30

lol the mail men r gunna get u

fordman15243 (author)2008-07-12

does anybody else think that his screen name fits him??? cuz I think it's f--king hilarious!!!

gnat (author)2008-04-27

What about multiple layers of acrylic? Or staggering the text so it has to be read at an angle? It would take more finesse with photoshop but I think it could work.

=SMART= (author)2008-04-27

very cool :D

Aerospaced (author)2008-04-22

Hey fun, great gag. As for the dink who went off earlier, fughetabotit! The optical reader uses a single camera to look at the image, therefore it can see the addy. Maybe you could send clandestine data using an encrypted message etched in this fashion? If you really want to screw with the mail, just use bar codes. The machine can read those too.

bushwhacker! (author)Aerospaced2008-04-23

Whoa! That's an awesome idea! I should totally try that.

rc jedi (author)2007-08-15

I can't remember all the stuff that has been stolen in transit to my house. Warning: if your stuff gets sorted in corpus christi tx, then ship by fed ex or ups. A trick they use , birthday card money theft. They tear a small hole in the corner off, straighten a paper clip, now bend a sharp hook back on itself. this is inserted into the hole. now spin the clip, it rolls up the money grandma sent you and forms a tight roll that can be pulled out the hole. Now they get the money, and they can still deliver the envelope "unopened"

burningsuntech (author)rc jedi2008-04-22

Well they might think they can get away with it but the Gov takes postal theft very very seriously. I've been in a regional sort center and you are watched constantly. If your caught, you go directly to jail and do not collect your $200. If anyone thinks a Fed Pen is a club, Think again.

burningsuntech (author)2008-04-22

Hmmm. What fine representative of the USPS and our government you are!

solo.card (author)2008-04-21

I like it. If only I had a laser cutter! I hate this website. Every time I browse it my "need" for a laser cutter and or sewing machine increases...

Trebawa (author)solo.card2008-04-22

I know... it can get so I have to close the window and weep for a while...

ChancreScolex (author)2008-04-22

I think maybe you should go back on your medication...

Tinker83 (author)2008-04-22

its called pay by phone - or direct withdrawal if youre lazy like me. the USPS is dying and you're just bitter. crybaby.

cooy (author)2007-01-07
srhadaham (author)cooy2008-04-21

i know u wrote this almost a year ago but oh well. if that think breaks i dont think i would trust ur mail cause that looks like 1/2 inch plexi and that would take a lot of force to break a piece that small

solo.card (author)2008-04-21

Also, a query; Can you print your own postage stamps directly onto your envelopes over your side of the pond? If so, would laser-etching the stamp onto a piece of acrylic do anything to bug the postal people?

Yerboogieman (author)2007-12-26

does the name on that one say McLOVIN?


no, it says ed lewis

cvxdes (author)Yerboogieman2008-04-21

Same number of letters.

jaysbob (author)2008-04-21


Big Bwana (author)2008-04-02

oh come on, it's not like he mailed an activated dollar store personal attack alarm, go on throw it away it'll beep in the trash for then next week .....

Full Frontal Graphic (author)2008-03-20

I'm gonna take this as parody, and assume in good faith that this is meant to "be nice" ... for me the 'nicest' part is : ..."mess with the mailman---I got news for you--when you bills and mortagage payments don't make it on time remeber what I said--we throw those out too!! especially from the douchebags that mail shit like this trying to funny--remeber we know where you live!!" just don't go postal on us.

bobulator (author)2007-11-15

Is this conforming with the 'be nice' policy? Hmm...

Aestheticxtattoos (author)2007-01-15

psychomailman is a real nut job. Luckily for him I'm gona try this neat little DIY.

Kiteman (author)2006-12-09

You posted this Instructable just over a month ago - did the card ever arrive?

fungus amungus (author)Kiteman2006-12-09

Yow, I forgot to update this. It did arrive. It took a week even with Priority Mail postage, but it made it. I was really surprised on this one.

fungus amungus (author)2006-11-21


Gnaw (author)fungus amungus2006-12-05

I can’t stop laughing, I feel more enticed than ever to try this! Looks like you struck a nerve fungus.

ViolaRen (author)2006-11-23

you=pycho... yes... illegal... also yes...

mrmath (author)2006-11-06

Fungus, Can you please do an instructable on the etching part. I have no clue how one would go about etching anything in anything... Thanks!

_soapy_ (author)mrmath2006-11-08

You could try using a printer transfer or something. If you did the same trick on two transparencies, then glued them on either side of a bit of acrylic, you could have the same effect for a lot cheaper than the laser engraver. You could also send a secret message by printing aligned dots in various colours. To read it, you use a colour filter and align the template to just the right place. You then send the message, and the person at the other end decodes it. Anyone else sees random dots that shift when veiwed. Even further, you could use this to do an auto-stereogram!

fungus amungus (author)_soapy_2006-11-08

Sounds like you need to make your own instructable now :)

_soapy_ (author)fungus amungus2006-11-18

I'll have to leave that to someone else, since I don't have an inkjet printer. Perhaps if I can find some laser transparencies...

(Top tip: don't send secret messages from colour laser printers, each one has a secret yellow dot code that IDs the date, time and printer! See )

fungus amungus (author)mrmath2006-11-06

This etching is beyond what you can easily do at home. I used a laser cutter to etch the surface and that's not a tool you're likely to pick up for this purpose. If you had a lot of time on your hands I suppose you could print out each piece, cut them into stencils, and use etching paste on it. Just a guess, though, as I have no idea how well acrylic would react to that.

Andrew546 (author)2006-11-06

I bet your mailman just absolutely loves you :p

fungus amungus (author)Andrew5462006-11-06

We get along all right.

Myself (author)fungus amungus2006-11-07

You entering this in the Return To Sender contest?

fungus amungus (author)Myself2006-11-08

Hmm... good idea. The next iteration of this card (which is even cooler) or a completely different one I made today would be better. One of those should be posted in a couple days. The other one likely next week.

zachninme (author)fungus amungus2006-11-07

Thats because you mail it at the PO, not from home, so he never knows :-P

LasVegas (author)2006-11-06

Yet again, a really cool waste of a great laser cutter! :) This is how experts are made! Someday a coworker will have a dilemma about how to do something completely different and you'll have the answer. BTW: to save the copy/paste step in Photoshop, just Option-Shift-Drag the image over. This will duplicate and keep it aligned. Then all you need to do it flip it horizontally.

fungus amungus (author)LasVegas2006-11-07

That's the same key-comboI used in Illustrator, except that on the PC it's Alt-Shift-Drag. It would be awesome if someone had some practical use for this. Meanwhile, I just keep playing around. The next one should be a little more useful.

About This Instructable




Bio: I like to make things for the internets. I also sell a pretty cool calendar at You'll like it.
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