This Single Combination Cryptex has a very spacious interior. The pictured Cryptex is currently being used as a Geocache (http://www.geocaching.com) in Minnesota (http://coord.info/GC3K7QE).

This Instructable is going to guide you through the critical steps to create a CAD file for 3D Printing a Cryptex. It will use Autodesk Inventor 2012, and will detail the critical steps needed to create it. Basic experience with your CAD software of choice is recommended. This should include creating parts, assemblies, extruding, cut extruding, revolving, embossing, and basic parametric modeling skills. If you are interested in making an exact copy of my Cryptex, please skip to Step 17which details modifying my files to edit the combination. 


POST-INTRO NOTE (PLEASE READ BEFORE COMMENTING): I have recently received many comments about getting the STL for printing. I don't believe you actually want the STL file. This Cryptex is a fixed combination, and thus, if I give you the STL, it will be exactly as shown in the images above. Plus, there is writing on the side which you do not need or probably want. 
Second: This print requires use of a printer with a soluble support material. There is no way around it. Since the rings are printed on to the outer chamber with about a hundredth of an inch gap, and are inaccessible to clean out any non-soluble support material, you WILL need a printer that can print in a soluble support. I used a Stratasys uPrint printer, which prints in ABS and a support material.

Step 1: Dimensions

The first step in creating your Cryptex is to figure out what the dimensions want to be. You need these dimensions to move on:
> Number of Letters in your combination (I used 6)
>Outside radius of the rings (This dimension is not critical, I just used it as a reference point. This dimension gives a target point for all of the other ones.) This will give you an approximation of how large your cryptex will be.

For my cryptex, I wanted a fairly large cryptex, with easy to grip dials, easy to read letters, and an easy to access compartment. I wanted it large enough to fit into your palm, but not small enough to fit easily into a pocket.
This is an awesome 3D print! I'd like to try it out myself - could you please upload the stl file you used? Thanks!
I have the .stl, but the problem is that it has only one combination. To adjust the combination, you will need Autodesk Inventor or another software that can read .ipt and .iam files. <br> <br>If you wished, I could upload the stl, but you would be stuck with a cryptex that had the combination &quot;cipher&quot;, and the words &quot;Geocache&quot; and &quot;Cryptech&quot; engraved on the side.
<p>If we had the STL we could just edit out the words : )</p>
I am working on another cryptex that has an adjustable combination, but it is coming along slowly.
Hi: Terrific bit of work; well done!! Have you made any progress on your cryptex with an adjustable combination?
I am still working around getting the notch in the rings to be adjustable. I have several ideas, but the methods are fairly large. I think I am looking at it the wrong way... <br> <br>P.S. Thanks to your comment, I think I figured out the solution... Thanks for your unintentional inspiration! I am going to try this out, and hopefully can get another version printed.
I'm a very interested geocacher (bald half of Team BaldRed) therefore an &quot;end-user&quot;and do not have your design skills and software. Do you know of other (freeware) software that would be able to make use of your design files?
Hmm, I am not sure of any freeware cad that would have the ability to import Inventor parts, and still retain the ability to modify them parametrically. I would say that you should download something similar to Google Sketchup, and try to create your own. If you are only looking to CAD and print just this cryptex, you could try just downloading and installing a trial of Inventor temporarily. You could then modify the files, and export it to a file type (like STL or STEP), which could then be eaten by your favorite freeware CAD.
You could also try 123D Catch (by inventor). I have no experience with it (as I have Inventor), and am not sure how full fledged it is...
And, I just realized that there is a 3D printed Cryptex with adjustable combination in the related section... The designs are similar, with a few couple major differences. The ring design is similar, but I am building in an &quot;Anti-Cracking prevention system&quot; to prevent people from trying to brute force the combination... I have gotten word from some of my other geocachers that you can easily brute force this cryptex in under 3 minutes...
Hmm; in your primary Instructables photo above, when enlarged, one can see gaps between your letter wheels that MAY allow a user to see where the pin slots are located in each letter wheel, allowing a user to &quot;brute force&quot; or &quot;hack&quot; your cryptex. The gaps of which I speak may be a necessity in your current design, filled by support material in the printing process.
Yes, there is a gap. You cannot see down inside, however. The dials are shaped like a T, and the gap is in the vertical stalk of the T, so it obscured by the inner and outer chamber. I specifically checked this when I designed the cryptex, and the other rings help obscure this. Unfortunately, it can be cracked fairly easily by using the tension method... A.K.A: Nccylvat Grafvba gb gur vaare punzore, naq gura gheavat gur qvnyf hagvy gurl pbzr serr. (You should know what this is... ;) ) With my adjustable one, I am designing in a mechanism that defeats this problem.<br> <br> Speaking of which, I am almost done with the modeling. I have to make a few tweaks, like redesigning the combo ring for structural support.<br> <br>
As a geocacher, I came across a cryptex in a geocache last summer while on vacation in British Columbia, and I'm about to make one or more out of PVC. I'm very interested in producing at least two in the near future for a local area geocaching event coming up this August; would love to have the ability to 3D print them!!
<p>This is amazing! Would it be possible to print this with different filaments? I don't know about you, but I'm thinking Da Vinci Code. The rings could be one color (like the ivory color you have here) and the outer chamber would be something like <a href="http://www.monomachines.com/shop/office-supplies/3-d-printers/filament/3d-systems-391173-abs-gold-cartridge-for-gen-3-cube.html " rel="nofollow">this</a>.</p>
<p>It's possible that you could print a Cryptex like this one in two colors, with only a single nozzle system, but that would involve switching between 3 filaments. As I constructed this as a single piece without the ability to remove the rings, you would need to pause the print, and switch out filaments between layers, but that would be REALLY time consuming. The system I used was a dual nozzle, one for model and one for support. If you managed to find a 3 nozzle system, it would be a piece of cake.</p>
<p>If you dont have a support material printer just use adhesive legends banded around the device. At least you can still print it with an inexpensive 1 Extruder reprap. I'd like to try printing this in metal filament just to see how it turned out : )</p>
<p>The problem is that the Cryptex is printed as one piece, with the rings around the outer chamber. If you had no support material, the ring will be bonded to the outer chamber. Even if you add small support structures (single width lines), they will be prone to sticking around and catching on the edges of the outer chamber or rings, if you can break the rings free.</p>
<p>Perfect idea!</p>
How can I get the file I can use with a 3d printer for the criptex? <br>
First off, welcome to Instructables! If you take a look at the comments below, from WYE_Lance, I explained what I have currently. <br> <br>If you are one of those TL; DR people, I have it in two different types: STL (not been uploaded), and IPT/IAM (available on step 17). <br> <br>If you are still looking for the STL files, I can upload them at the end.
<p>Yes, it's would be cool to get stl files. I see two files in stl format, but can't see separate ring, etc. It's normal?</p>
<p>Yes. The rings are printed directly onto the outer chamber, so you only need the inner chamber and the outer chamber. This is why you need a printer that can print in a soluble support material. Also, as it is a fixed combination cryptex, the combination CANNOT be changed in the .STL file. </p>
<p>I have been trying to buy a printer, too expensive and no job yet. This seems like a good place to start in 3d printing custom puzzles.</p>
<p>Is there any way you could make an assembly video and when will you upload the STL file?</p>
<p>There were only 2 parts to assemble, the inner and outer chamber. Since this was a fixed combination Cryptex, the dials were printed on the outer chamber, and the inner chamber was printed separately. <br>Also, since this is a fixed combination Cryptex, if I gave you the STL file for printing, you will be stuck with my combination, and my &quot;GEOCACHE: CRYPTECH&quot; written on the side.</p>
<p>How much room did you put between the dials and the outer chamber than? I don't mind the text because I just want to use the model as a reference.</p>
<p>There is a .025 inch difference between the radius of the ring and the radius of the chamber. My printer was able to do this, and I think it was too large. Your printer might be different, so your mileage may vary. I will post the STL files at the end.</p>
<p>Alright, thanks for the information. I appreciate it.</p>
Where can Iiget the file for i can make one?
&quot;If you take a look at the comments below, from WYE_Lance, I explained what I have currently. <br> <br>If you are one of those TL; DR people, I have it in two different types: STL (not been uploaded), and IPT/IAM (available on step 17). <br> <br>If you are still looking for the STL files, I can upload them at the end.&quot;
i really need to get/win a 3d printer!! what software do you use to design your prints? and you should try to pentent this before someone steals it!! please reply <br>thanks
I use Autodesk Inventor 2012, but by following the same steps, you could do this in basically any other cad software. The tools and directions might be different based on the softwrae, but theoretically, with a lot of work, you could do this in Google Sketchup (somehow). <br> <br>I have a list of about 20 patents that I want to get patented, but because I am a poor college student, I have nowhere the amount of money I need to get a patent... <br> <br>To print out this model, I used a Stratasys uPrint system, with a .01&quot; layer resolution. It took 26 hours to print the dials, another 6 to print the inner chamber, and then about 24 hours of soaking to remove the support material.
i didnt know that you had to pay to get a patent, but at the same time i didnt know otherwise,
And I don't actually own a 3D printer (I wish I owned a laser engraver or CNC machine, or 3D printer). I printed this using my school's 3D printer.
Thats the best geocahe I've seen, on your intro step you still have INSERT STEP NUMBER HERE.(you might want to fix that) Nice job.
When I was writing it, Instructables gave me several errors saying that they couldn't update my Instructable. I had edited that to say 17, but apparently that error prevented it from transferring from the preview to the actual Instructable. <br> <br>Thanks! I had planned on doing something like this for a while. <br> <br>I am now working on a version for myself that I can adjust the combo on. This will take me a while, because the mechanical complexity is higher, and the tolerances will be smaller.
Good luck. Even this one is much to complicated for me. Really like to see the one with the adjustable combo.
So you print the rings right on the outer chamber? I didn't know you could do that with 3D printing. I guess it depends heavily on the printer. <br> <br>Nice Job!
A lot of Fused Deposition Modeling (FDM) 3D printers, like the Stratasys system that I used, use two or more materials to print. The system I used prints in two materials, the actual plastic, and a black, soluble support. This support material gets printed to make sure that the parts stay supported as the part cools. This also gives you the ability to print moving parts. There is a demo of the printer which prints a fully functional crescent wrench. <br>When the part is finished, you dump in in a bath, which dissolves the material away from the part, and frees up the rings.
That's some high end printing! I always think of the kind you can build off the internet when I think of 3D printing. I forget there are pros out there, sometimes!
I am 17, and I printed this using my high school's uPrint system that they got for the Project Lead the Way curriculum. I designed this in an independent study, completely by myself. Usually, we use that printer for the very simple parts curriculum, but our FIRST robotics team (FRC team 3130 and team 2175) uses it for prototype parts. Sometimes they can be complex, and sometimes they are simple. Team 2175 built about 50 sprocket spacers, because they needed to be a custom size. We have personally built about 500 of the FIRST robotics logo with our name on them for the competitions as giveaways. We did that with a sponsorship from Stratasys themselves!
I should clarify... I was 17 when I made this back in May, and I am now 18. Just for anybody looking this over from the contest. ;)
Just because you're 17 and not a paid professional, doesn't mean you're not a pro! That thing is awesome, and is something a paid professional would be proud of. <br> <br>If you go into this field, bring it with you on interviews for internships. It's impressive.
Wow, that sounded weird. What I mean to imply there was that anybody can do this sort of thing. If you put your heart to it, you can do anything.
As an engineer I tend to use these machines to create purpose-built objects that perform a function well, but are never seen by anyone else. This project is nice because it forms a nice meld of engineering and art to make something that is beautifully functional and also a pleasure to see and hold. Keep up the good work - and as mrmath says, this is the kind of stuff that employers want to see! It sounds like you're on the engineer track already, but keep the artistry. Good luck to your FRC team!

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