3D Printed Cryptex

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 17, which details modifying my files to edit the combination. 

IF YOU ARE CURRENTLY SEARCHING FOR, OR PLANNING ON SEARCHING FOR, THE GEOCACHE CRYPTECH (GC3K7QE); YOU SHOULD BE FOREWARNED THAT THERE ARE SPOILERS INCLUDED IN THIS INSTRUCTABLE.

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.

Comments

[dean14111]

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
thanks

[pjensen]

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).

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...

To print out this model, I used a Stratasys uPrint system, with a .01" 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.

[dean14111]

i didnt know that you had to pay to get a patent, but at the same time i didnt know otherwise,

[pjensen]

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.

[WYE_Lance]

This is an awesome 3D print! I'd like to try it out myself - could you please upload the stl file you used? Thanks!

[pjensen]

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.

If you wished, I could upload the stl, but you would be stuck with a cryptex that had the combination "cipher", and the words "Geocache" and "Cryptech" engraved on the side.

[pjensen]

I am working on another cryptex that has an adjustable combination, but it is coming along slowly.

[Zaphod Beetlebrox]

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.

[pjensen]

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.

Thanks! I had planned on doing something like this for a while.

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.

[Zaphod Beetlebrox]

Good luck. Even this one is much to complicated for me. Really like to see the one with the adjustable combo.

[mrmath]

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.

Nice Job!

[pjensen]

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.
When the part is finished, you dump in in a bath, which dissolves the material away from the part, and frees up the rings.

[mrmath]

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!

[pjensen]

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!

[pjensen]

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. ;)

[mrmath]

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.

If you go into this field, bring it with you on interviews for internships. It's impressive.

[pjensen]

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.

[dougjensen]

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!