# How To Make a Cryptex

6 Steps
In this Instructable I'll show how I made my cryptex.

There is already an Instructable on making a cryptex published lately, but I wasn't satisfied by that one. That cryptex was held together on the outside, like this. I prefer my cryptex held together from the inside, like this. That is by the way the 'real' cryptex, like it is used in the film. Those are harder to make.

A cryptex is a kind of lock with a password, that holds a roll of paper. Author Dan Brown said in his "Da Vinci Code", a book from some years ago, that Leonardo da Vinci invented it, to let messengers carry secret papyrus rolls that the messengers themselves may not read; only the sender and the recipient know the password. If the messenger would smash the cryptex to read the message, a vial containing vinegar which was rolled inside of the papyrus roll would also break even earlier than the cryptex itself, the vinegar would spread over the message, disolve the ink, making it unreadable.
The term 'cryptex' is actually made up by Dan Brown. I don't even know for sure that it's true that Da Vinci invented it, he never actually made one, he would have made a blueprint in his diary, but I never found that page of his diary(so I made my own blueprint, see the next step). What I do know, is that the vinegar thing doesn't work. It doesn't disolve the ink so much that it gets unreadable, it becomes only a little more vague. I tested it with Black Indian ink, several kinds of pen inks, marker pens, ecoline, pencils, and some more; it never worked, just like Wikipedia says.
In the Da Vinci Code, the cryptexes were used different than how they were meant by Da Vinci, in the story they use it as a part of a big puzzle, the answer to a riddle is the password of a cryptex, which contains another riddle that leads to another cryptex, etc. To my opinion the use of cryptexes in such a way is a bit ridiculous, the characters in the book could've just put the cryptex in the freezer so that the vinegar gets frozen, then they could saw it open without danger. But they didn't think of that easy solution in the book.

edit:
In the comments below, 'cavingboy92' came up with this genious way to make use of the vinegar vial: on the paper around the vial, don't write with ink, but also with vinegar. If you want to read the message, pour a PH indicator on it(like red cabbage juice), and you can see the text. Or you can just hold it under a low heat source like a light bulb, then you can see it too, because the acid will oxidate.
If the vial breaks, the piece of paper gets all drenched in vinegar, so it's absolutely sure that it's unreadable!
Here is the proof that it works, tested by cavingboy92.
You could also just put the same inkin the vial as the ink where you wrote with on the paper, that would also destroy the message.
If you want more ways on how you could use a vial-break-delfdestroy mechanism, read throught the comments below, there are a lot of people giving suggestions for it, and also on improving the cryptex.
Finally, if you disolve a lot of salt in the vinegar, I think you can lower the freezing point of it so much that it can't get frozen in a normal kitchen freezer, then the freeze method also won't work so easily, you would have to find a special freezer in a lab or something.
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## Step 1: The Blueprint

Here is a blueprint for the cryptex, see the image below. A bigger version is found here. Try to understand it; when you are building this, you should really know what's going on. If you don't understand it, read through all steps before you start to build. I recommend to read through it anyway.

edit:
I got a question about the dimensions I used, these are my measurements:
the whole cryptex
length(from point to point): 14.5 cm / 5.7 in
diameter: 4 cm / 1.6 in

tubes(the diameter is including the thickness)
4th tube(largest): diameter 4 cm / 1.6 in, thickness 0.4 cm / 0.15 in PVC
3th tube: diameter 3.2 cm / 1.25 in, thickness 0,4 cm / 0,15 in PVC
2th tube: diameter 2.5 cm / 1 in, thickness 0.13 cm / 0.05 in ALUMINUM
1th tube: diameter 2.2 cm / 0.85 in, thickness 0.2 cm / 0.07 in STEEL

dials
the dials are made from the 4th tube and the 3th tube, on the outer side, to the 4th tube, they are 1.5 cm / 0.6 in wide, the inner part, made from the 3th tube, is a little smaller, just that a nail fits between.

You don't need to use these dimensions, there are just some requirements for the dimensions of the tubes, see that in the text at the next step.
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ThaXified says: Mar 15, 2013. 4:57 AM
Oyster?
Smccln says: Mar 7, 2013. 7:01 PM
Interesting...
But, really with trial and error, you could crack the code...

But, i still want one
xvf. says: Jan 2, 2013. 1:02 AM
Let me enlighten you. The vinegar is not meant to dissolve the ink but the PAPYRUS itself.
merijnvw (author) in reply to xvf.Jan 7, 2013. 8:11 AM
Let me enlighten you. Read the text or comments for chrissake. Papyrus is not dissolved by vinegar
superrust says: Nov 29, 2012. 6:15 PM
What did you use to cut the incisions?
altimus32 says: Sep 11, 2012. 6:51 AM
this is an awsome instructable especialy for me because i have a lot of nosey family members
thattori says: Sep 11, 2012. 2:10 AM
What kind of material do you use?
Marcus Worsley says: Jun 25, 2012. 9:44 AM
i have made a version of my own here is a link, please leave your thoughts and how you think i could improve it

http://www.instructables.com/id/Da-Vinci-Code-Cryptex/
nickmccullough says: Jun 2, 2012. 8:47 PM
Great build and a great instructable. definitely favoriting and planning on building a couple as gifts in the future
monkeys98 says: Jun 2, 2012. 3:41 AM
you should really sell this as a kit
Dusk Shadows says: Jun 2, 2012. 1:52 AM
haha u think that can stop me i can brake into a 79 numbered vault in 5 minutes lol lol lol I CAN"T BE STOPPED MUHAHAHA!
canucksgirl says: Jan 12, 2012. 11:50 PM
Very cool. Thanks for sharing. :D
maddiemanahan says: Jun 4, 2010. 11:42 PM
Where would you recomend buying the four tubes ?
I have made a lot of different things with tubes and I always go to LOWES.
i would say home hardware in the plumbing section, or any hardware store,if you cant find any ask a clerk or someone
SimonRawr says: Jul 9, 2011. 5:00 PM
Another way you could make the vinegar vial work is is you wrote on something like tissue paper so the vinegar would dissolve it completely. I also like the idea of adding salt to prevent the freeze method. I was wondering if somebody could figure out a way to make a timed cryptex so that if it wasn't opened in time, the message would be destroyed. That would take some work, but would eventually be worth it for secret spy stuff.
94todd in reply to SimonRawrNov 6, 2011. 7:34 PM
thats actually exactly the point, had merijvnw read a little deeper into Dan Browns book, paper is not the material the note is written on but rather papyrus, which dissolves in vinegar, im not sure if someone else has already commented on this, but if so i just wanted to bring it to greater attention
merijnvw (author) in reply to 94toddNov 7, 2011. 9:13 AM
had 94todd read a little deeper into this instructable, he wouldn't have placed this comment. pfff
afrausto in reply to SimonRawrSep 29, 2011. 8:38 PM
Old post, I know.. I would look in to something electronic. Small timer (chip might work best), maybe a motor to crack the vial? Not sure how small it could be though. Sounds like a weekend project for me =)
Pickles5000 in reply to afraustoNov 7, 2011. 1:35 AM
In the book, pulling to hard on the ends of the cryptex actually moves a lever that has a point attached to it that presses down on the vinegar vile. When enough force is used (less force than required to break the cryptex) it cracks the glass vial containing the vinegar. this acion releases the vinegar which dissolves the papyrus.
bowmaster says: Sep 4, 2011. 6:33 PM
I plan to use this to make a cryptex flashdrive, encrypt in digitally, then put back-track linux on it for a top-secret hacker drive.
merijnvw (author) in reply to bowmasterSep 5, 2011. 11:05 AM
XD good luck!
bowmaster in reply to merijnvwSep 5, 2011. 5:05 PM
Much better then the "Auto-Hacking Wardrives" on Instructables. This one can be used to actually hack, not just copy random files.
laloworld94 says: Aug 23, 2011. 9:31 AM
the paints you are using...wich kind is it? i live in mexico and i think here they dont sell teh citadel paints...
merijnvw (author) in reply to laloworld94Aug 29, 2011. 10:48 AM
it's paint from the miniature wargame called warhammer, I have the paint even though I don't play the game. It's a nice type of paint I think
ahurd1 says: Aug 7, 2011. 6:45 PM
I'm really excited about trying to make a cryptex. I think I understand the steps, but it should be much easier to understand when I have the actual tubes in front of me.

Thank You
ToxicAvenger says: Aug 2, 2011. 1:59 AM
The best Cryptex tutorial EVER
yaly says: Jul 5, 2011. 10:26 AM
okay cool, now how do you change the password?
Gossey2002 in reply to yalyJul 12, 2011. 10:08 PM
I have given this thought with several designs, the best way to describe it is to make the lettered part have a piece under neath it that is an internal gear (http://www.rushgears.com/images/internalIMG.gif), with this you can adjust where the keys letters are on each letter ring. While I cannot describe this in great detail I suggest looking up how to change the code of your cryptex (the small ones Google distributed as part of their give away), the descriptions will show you all the internal workings and give the information you need.

Also, what he said " v ".
Burnsides says: Jul 6, 2011. 6:14 PM
Hello next week's project.
The Jamalam in reply to STAN03251Jul 2, 2011. 2:13 PM
stop spamming, nobody cares. and it's irrelevant and bad.
lkearbey says: Aug 28, 2009. 1:53 PM
You mention engraving on the PVC with a heated paperclip and that the fumes are harmless. It appears that the vapors from heating PVC can cause some forms of cancer (what doesn't these days though!) so it might be a good idea to do that in a well ventilated area.
merijnvw (author) in reply to lkearbeyAug 28, 2009. 3:04 PM
Thanks for the information, I'll add it in to the text. I had my doubts about it too, but I read on another website that it's harmless. However there are researches about PVC that contradict the other. Also PVC in contact with food, some say it's unhealthy, some say it isn't.(I know that because of my other 'cat feeder' project) I'll tell them to do it in a well ventilated area like you said.
JohnMichael in reply to merijnvwJun 29, 2011. 4:07 PM
PVC is Poly-vinyl-chloride. Burning or melting it can give off small amounts of chlorine gas. It doesn't take a lot of chemistry knowledge to figure out the reaction of breaking down PVC molecules with heat. There may be some that say it doesn't happen. Though, I would not take the chance that they are wrong.
tobyscool says: Jun 2, 2011. 6:06 AM
Hey your blueprint is very helpful,I made my own out of 4 tissue rolls and paper mache for the ends. :D
paige_brahh in reply to tobyscoolJun 26, 2011. 4:53 AM
how did you make it from tissue rolls and paper mache? :)
Poehls05 says: May 10, 2011. 6:40 PM
Thanks for posting this. I made my own, but the password is my last name, which kind of ruins the point of it because everyone I ask can guess it. Oh well.
merijnvw (author) in reply to Poehls05May 16, 2011. 9:58 AM
haha, stick new alphatbet strips on the dials then! with a different password
liam_mcquellin says: Apr 11, 2011. 10:19 PM
Hello,

Just reading through your instructable, I cant find any reference for your tube lengths? I am assuming they are about 10cm long. Can you confirm this?

Thanks
merijnvw (author) in reply to liam_mcquellinApr 19, 2011. 8:31 AM
I would estimate them as 13.5 cm or so, not super sure though, can't measure them now as I am on vacation. But this length is dependent of the length of your password of course, that's why I didn't include it I think. Moreover my measures are just an example, take the measures how you like, good luck!
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