Introduction: 3D Stress Cube

About: I really enjoy making things and solving problems. After my first engineering class's first project, I wanted to try and make an instructable of it. My dad always sent me Instructables so I was fairly familiar…

For my first engineering class, we had to create a sensory tool to help people calm down and enjoy playing with. My item is the "Stress Cubed". It has 3 sensory sides and 3 interactive sides. In this instructable, I'll show you how to create all the pieces, using math, and print it.


You'll Need:

  • Inventor (I'm using 2020)
  • Dremel 3D Printer
  • Dremel Software
  • 3D Printer
  • File
  • Hammer
  • Marble with a diameter of 1"
  • Filament
  • 4 Pen Springs (0.25-0.35" Diameter)
  • Basic Geometry knowledge

Step 1: Blueprints

Before I even thought about creating the model I went through 8 pages of my notebook, making revisions. When I decided what to make I had to measure everything to make sure it would all fit together. I wrote down every dimension, change, and detail I could think of. When it finally came time to model I created the model and printed it; not all the pieces fit together perfectly. I had to go back and re-create the pieces, re-size them.

This project took 8 weeks to create with lots of math, trial, and error.

I hope you have fun creating your own!

These were my constraints for the project, you may not have them:

  • Has to be 3D printed and or laser cut
  • Has to be handheld
  • Has to be under 1 pound
  • Has to be safe to handle
  • Has to be completed in two months

Step 2: Make Base of Cube

So I started with a 2.5" cube in Inventor and used that as a base.

This is roughly the size of a Rubik's Cube and has nice weight when printed.

Step 3: Fillet the Edges

To make the edges softer, we need to use the fillet tool on the sharp edges. You can either use the fillet tool and then select the edges to fillet or you can click an edge to fillet and select the rest. I filleted them at 0.125" and this worked well to allow other sides enough space. If you can, I would recommend filleting it more, maybe 0.2".

Step 4: Sketch and Extrude Waves (Top)

So you're gonna want to make this side the top because if you print with supports,(which you will most likely need) they're a pain to get out and will ruin your cube. For this side, I used the spline tool in the line drop-down menu. Once you make a line with the spline tool, then make a new line--still using the spline tool--to complete the shape and get sharper points. (Make sure you complete the shape or it won't extrude.)

I extruded 0.25" for all the waves, but do as many different heights as you'd like.

After extruding, I filleted the sides of the waves -- not necessary -- the fillet I have is 0.0375" for all the waves.

Step 5: Marble Side(Bottom)

For this side we have a marble that can be rolled by a finger. This will be the bottom since it has supports that are easily removed. I have lips designed for this side and the button side, so we have a lip insert space here. The measurements are 1.3" diameter and the inward extrude is 0.2".

For the part that actually holds the ball, we are going to make the diameter 1.25" and in the inwards extrude 0.4" using the bottom of the last extrude as the sketch surface. The fillet for the bowl-ish shape was 0.625".

Tip: To get a perfectly centered hole, create an X by connecting the corners and use the center as the origin for the circle (this will be used a lot).

Step 6: Organizing the Other Four Sides

You can put the other 4 sides wherever on the cube, but I'd suggest placing them like this to make assembling easiest, with each interactive side opposite of an inactive side.

I have the unfolded version in the top left of the sketch for you.

Step 7: Button Side

To make this side, we have 4 holes for the 4 spring-loaded buttons.

Each has an indent in the side for a lip and it is very similar to the ball side. First, we need to make the origins for our button holes. To do this I did the same thing as before where I connected the corners to make an X, but this time I connected the lines with a 90-degree line. This took a lot of guessing, but I'll try to help make this easier.

Once you have the main origin line (the center intersects), make lines from the center (0, 90, 180, 270-degree lines).

Then measure how far the center is from the edge, and stop where the fillet begins. Now halve it and try to make a square that hits all the half points.

Now to the actual extruding.

The diameter of all the buttons is 0.75" and the lip extrude is 0.2". The rest of the extruding has a diameter of 0.7" and an inward extrude of 0.35".

Step 8: Fidget Flower Side

For this side, the fidget flower side, we are going to simply make the pole for the flower to be on. we need it to be hollow for the insert piece later on. Again I make a cross and used the center to make both circles.

The outer circle's measurement is 0.45".

The inner circle's measurement is 0.25".

I extruded the pole 0.3" and left the inside alone.

No fillet and no complicated stuff.

Step 9: the Bumpy Side

For this side, I made a lot of random circles and extruded them to different heights. To get different heights you'll need to extrude different height circles at different times.

Since I tried to make this side random, there isn't really a wrong way to do it. I had some circles big and some small, I had heights varying from 0.2"-0.05" and I stayed inside the fillet lines. Have fun with this side, make different shapes, do whatever you want. The filleting also changes for each different diameter. This side has no rules really.

(I'd recommend filleting the shapes you make though.)

Step 10: The Groovy Waves

This side takes some more functions than the rest.

I have each wave taking up a third of this side (from fillet to fillet).

To make a wave you need to create a plane to work on. Select "plane" in the top center/right and use the "mid-plane between 2 planes" and select the top and bottom sides. Now you have a center plane. If you want to keep it simple then I'd say make 2 waves and go on with your life, but now we gotta make 2 more planes for this instructable.

Use the same plane tool (mid-plane) and select the center plane you just made and the bottom side. Now you have 2 planes. Use the same tool again but select the center plane and the top side. Now we have all the planes we need.

Click on the plane you'd like to draw a wave on and select "create sketch". Click "splice graphics" (this allows you to see your plane and have an unobstructed view). Now take the spline tool from the other wavy side and make waves, making sure to connect to the face of the cube at the beginning and end.

Make 3 different patterns and use the extrude tool on the wave, extending both sides using the blue and black arrow extrude setting to adjust each side to your liking. Now adjust the 3 waves to be in contact with each other without overlapping.

Tip: Make a line on the face of the cube to connect your lines together for each plane and wave.

Step 11: The Tiny Pieces

We are now going to design the: buttons, ball lip, button lip, the flower fastener, and the fidget flower.

For the actual ball it self, we will use a big marble, but if you'd like to 3D print a ball the diameter is 1", so make a 1" cube then fillet the sides to make a ball.

Tip: If you are going to 3D print the ball, make it between 80-100% infill, printed with high quality and use acetone to smooth it out.

Step 12: The Ball Lip

For the ball lip (what's going to hold our marble in place), we need to make sure it fits, but isn't loose. I made the lip six times before finding the right measurements for it.

The diameter of the base (the part we are placing into the cube) is 1.3" for the outer circle and 1.2" for the inner circle. The height/extrusion is 0.2".

The top, the actual lip part, has a diameter of 1.75" and the hole is 0.8" in diameter, with an extrusion of 0.19".
I also filleted the outside by 0.125".

The fillets are 0.125" for the outside and for the inside of the lip (this helps the ball roll better).

I also changed the fillet setting to make it fillet inward instead of outward. You can do this by clicking the picture under "type" in the fillet menu and selecting the 3rd option.

Tip: Print a low quality 0% infill to test the marble with and make adjustments as needed.

Step 13: Button

For the button you just need to make a base with a diameter of 0.65" and an extrusion of 0.1".

Then for the button part, make a dimension of 0.5" and extrude to 0.5".

I filleted the top to 0.125" -- not necessary, but I think it feels nicer.

Now the hole for the button will have a dimension of 0.25" and an extrusion of 0.3".

Step 14: Button Lip

For the button lip, the insert part is pretty thin, so bear with me.

For the lip, the inner ring diameter is 0.55" and the outer ring is 0.85" The extrusion is 0.07".

The base has an inner diameter of 0.7" and an outer diameter of 0.75" and a fillet of 0.125", with the extrusion at 0.2".

The hole has a diameter of 0.8".

Step 15: Flower Fastener

For this one, it is probably the easiest thing to create.

Make the top (the part that is outside of the cube, the flat part) a diameter of 0.75" and a fillet of 0.0625" and an extrusion of 0.125". (I filleted both sides, but the outside one is the only one I would strongly suggest filleting.)

(I had a survey for people that used my cube and a majority said they didn't like the fillet of the fastener so this is optional and up to your own preferences.)

Next, use the base and it should make the center of the circle the origin so make the pole/inserter with a diameter of 0.25" and an extrusion of 0.3".

Step 16: Fidget Flower

This one I made before I even made the cube so the one I have is a bit complicated so I'm going to try and use my current knowledge to make it easier for you.

Make a center circle with a diameter of 0.7" (the pictures say 0.666", but 0.7" is more stable) and then make a square (I used the 3-point center rectangle) with a length of 1.2" for both sides (because it is a square). Now at each x-axis and y-axis intercept, make a circle with a diameter of 0.666".

In the very center (for the pole hole), make a circle with a diameter of 0.5".

Now use the trim tool and trim away all excess lines to make extruding easy.

FINALLY, extrude the shape to 0.25" and fillet all the sides to 0.0625".

Actual last step: Fillet the inside hole to 0.1".

Step 17: Exporting

To export the files to Dremel (the printing application):

  • Go to the "File" drop-down menu and select "Export"
  • In the "Export menu" select "CAD Format"
  • Save your File, using specific names. (Ex: Final_Cube, Fidget_Flower, Button, Button Lip, etc.)
  • Make sure the file type is ".stl"
  • Export all your files

Step 18: Print: Cube

Now to print.

I use Dremel.

In my Dremel, not sure if this is always the case, it changes the centimeters from Inventor and turns them into millimeters in the Dremel software.

Before you do anything else, go to the scale option, select the item you are going to print and take the decimal point and move it over 1 digit to the right and press enter.

Rotate the cube to make sure the ball side is on the build plate and the wavy-lines side is up.

The printing will take a while if you follow my directions exactly, but adjust however you'd like.

My settings were:

  • 100% infill (the lowest infill I'd give is 80%, but with all the filing you'll be doing I suggest 100% infill)
  • High quality
  • Material: PLA

The print time for the cube was 17 hours+ at 100% infill.

Step 19: Print: Pieces

Again, before you do anything else, go to the scale option, select the item you are going to print and take the decimal point and move it over 1 digit to the left and press enter. (Do this for all the pieces.) If you do Ctrl+A then you'll select all the items on the build plate and you can scale them all at once.

You should be able to fit all the pieces on the same build plate (excluding the cube).

My settings were:

  • 100% infill
  • High/Ultra quality
  • Material: PLA

Few recommendations:

  1. Print the buttons horizontally to make the inserted part stronger for filing.
  2. Rotate the pieces to get the least amount of support possible.
  3. If you don't print the buttons horizontally, then print them with the hole of the button pointed up so no supports are stuck in there.
  4. Multiply the buttons and button lips by 4. (You can do this by right-clicking the button and clicking "multiply selected item" them type in 3 for the multiples of the item.)

Tip: Print the lips vertically instead of flat on the build plate. This gives it more strength since the filament is not in rings, but in lines.

Step 20: Assemble: Fidget Flower Side

For the next 3 steps, you'll need a file to make sure everything is perfectly fitting together.

For the fidget side:

  1. Place the fidget flower on the pole
  2. Push the fastener into the hole on the cube's pole. If it doesn't go in at all, file the fastener's pole down and try again.
  3. Hit it with a mallet lightly to secure it and add glue if you'd like. I'd suggest using a piece of wood over the fastener as you hit it to displace the force of the mallet.

(This is a scaled down cube, actual cube is a lot bigger.)

Step 21: Assemble: Button Side

For this side, you'll need 4 pen springs (or springs roughly the same diameter (0.25"-0.35") and the length should be 0.75".

  1. Put the spring in the button's hole.
  2. Put the button with the spring in it into the cube's hole.
  3. Place the button lip over the button hole and push in (add glue to lip if desired). Just get the lip in enough to hold it still, then use a mallet with a wood piece over the button lip to displace force from the mallet.

(This is the full size cube.)

Step 22: Assemble: Marble Side

  1. Place the marble in the bowl shape.
  2. Place ball lip over marble (add glue as desired).
  3. Use your thumbs to push the ball lip in. If you're careful you can use a mallet and gently tap the sides in without hitting the ball/marble.

(Also the scaled down version of cube.)

Step 23: Finished!

Now your cube is completed. Show your friends and family! Fidget away!

Challenge Time: Make a cube that will work for a regular-sized marble.

This is my entry for the "Made With Math" Contest. If you enjoyed it, please consider voting for this!

Made with Math Contest

Runner Up in the
Made with Math Contest