20 Sided Dice

Hi, today I am going to do something a little different than what I normally do. I will be showing you how to make a twenty sided dice!

I will be using Autodesk Inventor for this project. I 3D printed my dice that I will show you at the end, but 3D printing is optional as not everyone is going to have a 3D printer at their house.

Open Autodesk and click "New Part" Once you are in, press 'S' or click "Start 2D Sketch"

I will be working from the XY plane but in reality, it doesn't matter which plane you work from.

Now that you are in sketch mode, click the down arrow under "rectangle". You should be seeing a list of options. At the bottom, there should be a "polygon" option. Click on this. The polygon that you need to make is five-sided. If you look at the settings for your polygon, you will see that it is going to create a 6 sided shape. Click on the 6 and change it to a five. Now that you have a five sided shape ready to use, click on the middle of the coordinate plane. Your cursor should snap into position when you hover over the center. now that you have clicked on the center, you are able to size the shape. For now, just copy what it looks like in the picture above and make your second click on the line above the center thus creating the shape.

Now that you have your shape, we are going to scale it to 1 inch. Click on the "vertical constraint" tool and click on the leftmost side that is facing down. (Note, do not click on the middle or the ends of the line. It will not work)

Since you now have a flat side, we can now dimension it using the "Dimension" tool (or by pressing 'd') click on the same side that you used the "vertical constraint" tool on. You should now see something similar to the picture above but with a different number. click to the left of the side that you are dimensioning and make the length 1 in.

Now that you have dimensioned the sides of the pentagon to be 1 in. long, we need to find some other values that will help us when we extrude our shape. Create a rectangle from the center to the upper left side of the plane. It doesn't matter how big it is because we will be changing it very soon. After you have created the rectangle, create a line by pressing 'L' or clicking line and make one from the center to the point directly to the right of it. Now that you have all of the needed parts to get the needed dimensions, you will be using the equal sign tool. The equal sign tool lies right below "vertical constraint". once you have clicked on the equal sign, hold down on 'ctrl' and click the three lines that are touching the center of the plane. Those three sides should all have the same length. It is time to use dimension again! Dimension the left side of the rectangle like shown in the picture. You should encounter a message that says that if you have this dimension, it will be a driven dimension. Click "Accept" and move on.

This part can be tricky so I made it have its own step. Make a line that goes from the top left of the rectangle to the center of the flat side as shown in the picture. Now that we have that line, we need to find the angle between the flat side and the line that we just created. Use the dimension tool and click on both the flat side and the line we created to get an angle measure. put the angle measure in a position around where I put mine. (This will be another driven dimension)

for this step, you are going to extrude your sketch. Press 'E' or click "Finish Sketch" and click "Extrude". You will see multiple options that allow you to change what your extrusion looks like after you select your shape. You will need to select the entire shape for your extrusion and you will know if the entire shape is selected if the inside is highlighted. I find that hovering over the edge of the shape is the easiest way for me to select everything. The main parts that we are going to focus on in our extrusion will be the distance that it is extruding and the taper it will have. You might have been wondering why we got those two dimensions that we couldn't change, this is why. click inside of the "Distance A" box and click on the first driven dimension that we made (It should be .851). Now that you have your distance, click in the "Taper A" box and click on the second driven dimension that we made (it should be 10.81). Click "Ok" and go on to the next step.

Start a sketch by pressing 'S' or by clicking "Start 2D sketch" and click on the bigger face of the pentagon. click the down arrow and click polygon again. Just like last time, click on the center of the plane. Unlike last time, click on the center of an edge of the shape's face that you are working on so that it looks just like the picture above.

Now that you have created the pentagon, extrude. The shape that you made should have immediately been selected for you. We are going to be using a few more parts in this extrusion. The first thing that you will need to do is change the output. Change the output from "Join" to "Intersect". This should change the direction of the extrusion. If the direction of the extrusion is not going into the other shape, change the direction. Now that you have completed this, put in the same values that you put in for your first extrusion. If you have been doing everything exactly as I have shown, the distance should be d2 (.852), and the taper should be d3 (10.81). Click "Ok" and go on.

Now that you have this shape, we need to add an axis. Add an axis using the "Axis" tool and make one from one point to another point on the opposite lower side as shown in the picture above.

Now that you have an axis, we are going to use the "Circular Pattern" tool. Click on the tool or press 'ctrl' + 'shift' + 'O'.

Now that you have this tool open, we are going to need to change some of the settings. First, change "Pattern Individual Features" to "Pattern Solids". Next, click "Rotational Axis" and click on the axis that we made. There should be an image of the new shape in green. The shape doesn't look quite right. That is because we are rotating this shape 6 times! change the 6 to a 5 and click "Ok".

Congrats!! You have made the shape for the 20 sided dice!

Now that you have the needed shape, all that you need to do is add color and add numbers. If you want to make the axis go away, right click it and click visibility.

To add numbers, press 'T' and select the side that you want your number on. Click in the center of the face to type the number. Increase the font-size to your discretion to fit the dice. Extrude the number in or out when you are done.

If you want to color the dice, click on the color wheel on the top with the dropper and choose ether a color or a texture for your dice.

When you are done, go to view, visual styles, and choose the option that you think looks best. You can also toy around with shadows and reflection.

When you are finished, Save!! There are several ways to save. The easiest way for me is to close the tab in the bottom left corner because it always asks you if you would like to save. I hope you enjoyed this

As promised, here are pictures of the 20 sided dice I 3D printed. (For some reason, 13 didn't print.)

Thank you so much for reading this instructable!

This instructable was a little different than usual. If you would like to see some of my other instructables, go here

https://www.instructables.com/member/NotePro/instructables/