How Dan Makes:

3D Stuff

Objective

The goal here is to design and 3D print an object that could not obviously be machined by subtractive methods (mills, lathes, etc.). Use some form of 3D scanning on any object and obtain a 3D file (STL) of that object.

The Plan

I like making cool stuff. I also love mythology. So naturally, this is the only way I could've gone with the assignment. The plan is to have an object which, in its resting state, appears to be any old desk ornament: A sphere resting on a tapered cylinder. But upon twisting the tapered cylinder, the sphere is raised directly upward and Atlas is revealed to be carrying the sphere on his back.

The Process

From the outset of receiving the assignment, I knew I wanted to do something with moving parts. In class, while thinking about the things I could make I decided I wanted to make something with a secret compartment that was revealed with a twisting action.

My brainstorming session lasted about two minutes. I started making a few drawings and got so excited about the Atlas idea that I immediately started on the SolidWorks design.


The result of my quick brainstorm.

I started with a simple outer shell, using a standard lofted boss to create a tapered cylinder.


Tapered cylindrical shell

Then I proceeded to make the base. When in use, the base will always remain stationary. It includes a circular track (T-shaped cross-section) running around it for the shell to ride along while it is twisted. It also includes a tall stablizing star-shaped stem for the sphere and figure to ride directly upwards and prevent them from spinning with the shell.


The base with circular track and star-shaped stem shown.

After I had the first two pieces, I started on the third: the globe held by Atlas. As this part developed, I realized that I won't really have much space to include a figure of Atlas. For this assignment, since 3D printing is very expensive and takes very long, we're limited by size and volume to conserve material and machine time.

I decided to change the shape of the stem here to give me a little more space to work with so that I can fit the small figurine. I originally was going with the star-shaped stem for maximum stability. However, when I was brainstorming on how to increase my working space, I realized that, as long as the stem can handle a little torsion and its cross-section is not circular, it will serve its purpose.


New stem shape is a spline with a circle at either end.

Finally after getting all of the main parts down, I started on the Atlas figurine lifting the globe. Since my choice of stem still took up a decent amount of space, the Atlas figurine isn't ideal. However, I think it's still clear that it's a man carrying the globe.


The completed Atlas figurine that will rest hidden by the shell.