All for Fun – Creating a 20 Sided Die

Death and the dice level all distinctions.
Samuel Foote

Many years ago, I friend asked me to create multi-sided die for a website he was creating.  You can still see the images on the banner of the website for DiceHouse Games here.

It was a tricky one to create.  It was a 20 sided die, a much used tool in role playing games like Dungeons and Dragons.

An Autodesk Showcase Rendering of the 20 sided die model

I also used it as an example in a blog post for using the “Change View Orientation”  tool inside of Autodesk Inventor drawings back in February 2012.  

***Edit 13-Nov-2012 : Added an embedded dwf of the 20 sided die***

A 3D dwf of the 20 sided die

*** End Edit***

Since that time I’ve started getting requests for how I built the die, as well as a location to download the actual *.ipt file.  

So here are the steps on how I built the 20 sided die!  

1. I found the definition of a Icosahedron (a 20 sided polygon) on Wikipedia.

The construction figure that started it all!

2. I created three sketches on the XY, YZ, and XZ origin planes in Inventor

The three rectangles on each plane to create the framework

 
3. Next, I used a 3D sketch to connect the vertices together, must like in the Wikipedia image.  If you’re wondering, this did take quite a bit of time. 

The process of creating the skeleton

4. This becomes the skeleton where I create several boundary patches.  The boundary patches create the surfaces of the die using the “sketch skeleton”.    This was also pretty laborious!

Boundary patches created close surface that could be stitched.

5. I then stitched the surface.  Since it’s “watertight” (completely sealed), it becomes a solid.

Stitching the surfaces make it a solid

6. Now it I had to add all the numbers (which were extrusions), and fillet the sharp corners. That’s it, I was done!

The completed die

So in conclusion, this was a satisfying little project took a little bit of research to figure out how to construct it.  Once I figured out the process, the steps weren’t difficult, but it did take time and patience to execute. 
 
Placing the 3D wires lines took a lot of time, and more than once I had to correct a line I misplaced.  The boundary patches took less time, but putting in all the numbers was an exercise in patience too.
 
So because of the requests, I’m uploading the file to a couple of sites for download.  However, before you go grabbing the file, I make only one request.
 
I spent several hours of a Saturday figuring this out.  All I ask is if you use this model, give me a nod and a little credit for the time I put into it.  
 
Now for the download sites!
 
The first is my Autodesk 360 site: Click here for Autodesk 360 download
 
If you use the GrabCAD file sharing website, you can also log in and get it here:  Click here for GrabCAD download