Super Mario Mystery Box Using Tinkercad

I came up with this box design when I was thinking about a new dog tag for my Jack Russell. I figured that a 3D model would be much cooler and since I like Super Mario I thought about doing it following the Mistery box design. I also found that it works very well as a keychain for my car keys.
The box has an internal threaded hole where I can save treats for my dog, waste bags, contact information, or pretty much anything you can think of that can fit in there.

In case you prefer to download the finished STL files, here's the link to them: https://www.thingiverse.com/thing:4889732

• 3D Printer
• Plastic filament (PLA, ABS or PETG)
• Superglue
• Split ring

Add two solid boxes from the Tinkercad Basic Shapes library.

Define the desired size, in my case I´m using 50x50x50 (mm) size boxes.

You can also set a bit of radius to curve a bit the edges and make them smoother. In my case I used a radius of 1.

To cut both boxes in halves add two more boxes but this time make them hole instead of solid.

Make sure the new hole boxes cover all the sides from each solid box and then set a height that is half the one used in the solid boxes, in my case I'm using a 25mm height. For the box in the right, the "hole" box has to be raised the same amount, in this case 25mm.

Group each solid box with its hole one.

The half at the right will have the male thread of the box. To add it We'll select an "ISO Metric Thread" located in the first page of: SHAPE GENERATORS →Featured.

Sizing the Thread: Since the height of the complete box is 50mm, We'll size the thread 45mm so it doesn't go across the entire box . For the diameter it can be any number that doesn't exceed the size of the box. In my case I will use a diameter of 41mm. The rest of the thread parameters can be found detailed in the image above.

Thread must be centered to its half box in the X and Y axis. For the Z axis it should be raised 2.5mm from the workplane.

To hollow the left half We'll duplicate the thread We just created by using Ctrl+D over this part. We'll drag this duplicated part to the other half and center it in X and Y axis.

Since we want the male thread to be able to be inserted We'll have to oversize this female thread so we get a nice fit. For my printer and since I don't want a very snug fit I'll be leaving 4.8mm of difference between both threads, this means that in this case the female thread will have a diameter of 45.8mm.

After this We can now group the thread and the left half box.

Now let's add a new hole Cylinder from the Basic Shape Library. We can add more segments to make it smoother, in this case I'll be using 32 segments. We'll also make it taller than the end of the male thread and We'll align its X and Y axis to the red half cube and the yellow thread so the three are centered.

Also, since we don't want the cylinder to go across the entire half cube We'll raise it 2.5mm from the workplane.

After this we can now group together the three parts: The cylinder, the thread and the red half cube.

Now that both halves of the box are ready we can align them in the X and Y axis. Using the "hole" view for this two parts we get sort of an X-ray view of how the thread will fit once printed.

Let's go ahead and add the question mark choosing the Text shape from the Basic Shapes library. Once selected We can change the default text to the question mark "?". We can also choose the font We want, in my case I went with "Serif".

We can now rotate it vertically so we can lay it on top of one of the cube side faces. To do this, I recommend temporarily changing the workplane to the side of the cube, it makes this change much easier by just pressing letter "D" dropping the question mark to the new workplane.

Ir order to make it easier to glue the question mark in the exact center of the box and to make it look neater I prefer to jig the shape of the question mark in the box. For this, once again, We'll have to oversize the question mark at the box side.

Let´s duplicate the question mark We just created using Ctrl+D, now We can increase the size of the new shape. For my printer I'll use a 0.4mm increase in all three axis.

Now we can push the oversized question mark a few millimeters inside the box, in my case I pushed it 2mm.

Since the box has two different halves, We have to duplicate the oversized question mark, this way We can group one of the oversized question marks with the green top half, and the second oversized question mark gets grouped with the red bottom half.

You can repeat this process for the other 3 side faces of the box.

Let's duplicate the question mark (Ctrl+D), and also add two hole boxes from the Basic Shapes Library.

Since this Mistery Box is 50mm height, We'll make each of this new hole boxes half size (25mm).

One of this hole boxes will be dropped at the workplane, while the other will be rises 25mm from the workplane, this way, We ensure We are separating the question mark at the correct height.

Now We need to group each question mark with its hole box.

For this step We'll select four cylinders from the basic shapes Library. Now let's size them, in my case I chose to do them of 6x6x6mm.

To lay them on top of one of the sides, once again, I recommend temporarily changing the workplane to the side of the cube. Once the cylinder is on top of the correct face, you can place them in the four corners of the cube, using the align button you can ensure the 4 of them are aligned correctly.

Now simply push the cylinders inside the box, in my case I used the same distance I used with the question mark, 2 mm. After this now you can group the two top cylinders with the top half of the box, and the other two with the bottom half.

Let's add a tube from the basic shapes Library. Sizes and shape configuration is available in the second picture although you can change them.

Once the tube is set We'll place it on top of the cube. Use align tool to place it in the middle, in my case I prefered to move it a bit back so it's not so close to my dog while he is wearing it.

Now we can download our project!

Let's slice both files using your favorite program and start your printers!

Using a bit of superglue glue every part of the question mark to a side of the box.

Now, install the split ring on the box ring and we are done!