Locking Container
Last updated
Last updated
This is a step-by-step guide to the Build a Personal Locking Container project found under Learn -> Projects or via this link
Let’s start by creating the top lid of the bank container.
Place a cylinder on the workplane and make it 80x80x3mm.
Continue to next step.
In order for your bank to stay locked if it happens to tip over, let’s add in a tab that will fit a lock.
We will be using the “Extrusion” shape in this lesson, which has cool options that allow you to change its shape dynamically through the Inspector window.
Expand the Shape Generators panel in the browser on the right of the screen, then expand the Tinkercad panel and locate the Extrusion shape. Note: The Extrusion shape will show as a gray cylinder in the panel, but we will change its shape.
Drag an extrusion shape from the Tinkercad panel, place it on the workplane, and use the inspector window to drag points on the circle and change the shape of the extrusion to look like a boomerang.
Reduce the height of the extrusion to 3mm tall, so it matches the thickness of the lid.
Move the boomerang shape to make it intersect with the lid shape
There are many ways to have the lid fit inside of the body of the container. One good way to attach the lid to the container is by using threads to twist the parts together.
A threaded lid has the advantage of only needing a lock on one side, and the threads themselves act as a lock as long as they are twisted together and are fully engaged. If we didn’t have threads, we would need two locks on each sides to keep the container lid secure on both sides.
Expand the Shape Generators -> ALL panel in the browser on the right of the screen, locate the Twisted Polygon shape on page 7.
Drag a Twisted Polygon shape from the Community panel, place it on the workplane, and increase the height from the default 20mm to 23mm. Note: This height change should be made with the settings in the Inspector window. Changes to shape generators made outside of the Inspector window will not be reflected in the Inspector window and may become confusing.
You want to make sure that the polygon is in the exact enter of the lid so that the threads line up, so let’s use the Align tool.
The Align tool will be used to align the Polygon with the center of the lid. You will know the alignment is complete if the alignment dot turns grey and the word “Aligned” will appears when your mouse hovers over the dots. Remember: The Align tool (along with other tools like the Group tool) require multiple objects to be selected.
Hold down the Shift key on the keyboard and click the Twisted Polygon and the lid to select both at the same time. Note: Make sure you do not select the boomerang shape. If all 3 shapes are selected the align action will not align the centers of the cylinder shapes.
From the Adjust menu, select the Align tool.
Click the black alignment dots that will center the Twisted Polygon to the lid.
This next part is more technical than creative, but it is incredibly important. If the threading on the lid and container aren’t set to specific sizes, then the threads won’t line up and you won’t be able to close your container!
You are making the “inner threads” now and you will model the “outer threads” later in this project.
Tip: Most “numbers” you see in tools like the Inspector can be clicked on and the number entered directly by typing in the number and pressing the Enter key.Try that in this lesson!
Click on the Twisted Polygon to select it and enter the following values in the Inspector window.
# of Points: 8
Radius: 35mm
Height: 20mm
Bottom Twist: 10 degrees
Top Twist: -10 degrees (negative ten degrees)
To move onto the next lesson, highlight your lid and click copy (or press Command-C). Then click through to the next lesson and paste your lid. Next, duplicate it!
To build the container we could start from scratch to build each component, but you have already done much of the required work when creating the lid. To save some time, you will re-use as much as you can!
Re-using is a great way of thinking! In this example, you will be re-using the lid to make the body of the container, and re-using the body to create the space inside the container! It’s almost always better to re-use than re-create!
We will begin by creating the shape that will be used to create the internal cut out of the container where you will place your notes.
Drag the orange cylinder from the “spare lid” you created in the last step to the middle of the workplane.
Increase the height to 50mm.
Duplicate the shape and move it to the side and change its dimensions to 65mm x 65mm and 65mm tall.
The inner (taller) cylinder will be used to “cut” a hole out of the wider and shorter cylinder. You will need to align them and then raise up the inner cylinder a bit.
The reason we raise the inner cylinder is because we want to have a wall on the bottom of the container that is just as thick as the lid. Note: You won’t be able to see that 3mm wall on the bottom until we do the grouping in the coming steps.
Hold shift down on the keyboard and click on the two cylinders to select both at the same time.
Select Align from the Adjust menu on the toolbar.
Align both cylinders so they are aligned to the bottom-middle and side-middle.
Click the taller cylinder to select it and raise it up by 3mm using the black arrow handle.
The inner cylinder is defining the “inner volume” of empty space we will create in this step.
If you made this inner cylinder smaller, then the inner space for notes or for coins or money would also be smaller and your walls would be thicker.
Click on the inner/taller cylinder to select it.
In the Inspector window, click on “Hole”. Note: Doing this will change the cylinder to a transparent striped cylinder.
Select both cylinders and click "Group" on the toolbar to cut the inner cylinder out of the outer cylinder making it look like a cup.
In order for the threads to work together, the threads inside the container need to be slightly larger than the threads on the lid. If they were the same size there would not be enough space for them to fit together.
This small gap between the smaller and larger threads is called “tolerance” and allows for just enough space to make the threads work without being too tight or too loose.
Since these threads will be cutting out of the container body, the threads need to be slightly bigger for the needed tolerance.
Drag a Workplane on top of the container.
Click on the “spare” set of threads, and press the “d” key. This “drops” the threads onto the newly positioned workplane.
Change the Radius of the threads to 36mm.
Dismiss the workplane by dragging a new workplane into empty space.
Let’s actually cut the threads. By doing this cutting, we are creating a slightly larger version of the threads in the lid, and they will match up well when 3D printed. One object designed to work with another is called a “complimentary set”.
This set is a great example of many ideas:
Re-using the threads to make complimentary threads.
That anything can be a cutting tool, even a spiral polygon.
The next time you look at a screw in your garage at home, you will now see that the threads inside are just a spiral that was cut out of a solid block!
Drag the new threads roughly over the container body.
Select the cylinder and the threads, then use the Align tool to align the shapes vertically.
Click on the Threads and click the “Hole” button in the Inspector.
Use the black handle above the threads to move them down 20mm.
Shift-click on the cylinder body to select both it and the Threads, and click on the “Group” key to perform the cut.
In order for the container to lock, there must be a complimentary tab on the body for the lock on the lid to pass through. Remember how great it is to re-use, you will be doing that again!
Drag a Workplane on top of the container.
Click on the spare “tab” you created earlier and press the “d” key to drop it on the active workplane.
Click on the black handle of the tab and move it downwards by 3mm.
Move the tab to the right side of the container, so that it intersects the container body completely.
You have made almost all of the container…congrats! Let’s clean up your model a bit. Once you think you have finished with creating a set of pieces, it is good to group them.
The nice thing about groups is that you can move the grouped objects all at once, very easily, and you can double click on the group to “enter” it and make changes. Clicking outside the group will “exit” the group and your changes will be shown.
Also note, we will be creating groups here, and groups can be any color you want them to be. Just click on the Group, and in the Inspector window click Color” and change the color to anything you want!
Drag a box around the lid you created at the beginning and click “Group”.
Drag a box around the container and “Group” them as well (you might have to change your view if your box keeps selecting the lid!)
Remember the description of how objects can be “complimentary”? We need to create complimentary holes so that the lock will go through both holes cleanly. But first, we need to position the two objects on top of each other so that we can cut the same hole through both parts of the container.
Click on the container, and rotate it so that the tab is laying on the ground (180 degrees)
Shift click on the Lid, and click “Align”.
Align the centers of both objects.
In order to fit a lock in those tabs we need holes!
This step is slightly tricky because we need to make TWO cutting tools. The reason for this is that we want the lid and the container body to remain as separate “Groups”…so therefore we need two cutting tools to cut through those two separate groups.
Note: make sure your cool extrusion shape does not cut into the side of the box, but only cuts through the tabs.
Drag out an Extrusion from Shape Generators -> Tinkercad -> Extrusion.
Resize that extrusion to 10mm by 10mm.
Drag the extrusion onto the center of the overlapping tabs.
Make it a cool shape that does not go outside of the tab. Note: Make sure the hole shape is large enough for a lock to fit through the opening.
Make the extrusion a “Hole”.
Duplicate the extrusion by clicking on Edit -> Duplicate
With that Extrusion selected, Shift click on the container body, and Group them to perform the cut.
Move the container body aside.
Drag a box around the lid and the other Extrusion-hole, and Group them to perform the cut.
You have now completed your locking container!
Copy and paste your design so far into lesson 3
Now that you have completed the container, what are some ways you can make it your own? During the project you may have come up with ideas of your own, but just in case you haven't below are some suggested changes and some challenges to how to improve the container.
Try adding some text to the outside of the container. Tip: be careful that the text doesn't poke through to the inside of the container.
Is there a better way to lock this container?
Can you get the container to lock without the threads?
Is there a different type of thread that might work better?
Hope you enjoyed this project! Time to move onto another project.
Upload an image of your customised container to the Firefly task
