In order to create printable 3D designs, it is important to keep these core design concepts in mind as you are creating objects. These are the fundamentals of 3D design, particularly as they apply to 3D design for 3D printing.
How is 3D Design Different From 2D?
This may sound obvious but the most significant difference is the addition of the 3rd dimension.
When you draw on a piece of paper, you are working in a 2D space. That is, you can move your pen left and right, and you can move your pen forward and backward on the paper.
Typically, we say that “left and right” movements are along the “X” axis. Forward and backward movements are along the “Y” axis. This should be familiar to you if you have taken algebra classes.
When you design in 3D, we had a third dimension. This dimension would be if you lifted your pen up and down off the surface of the paper. We call this vertical lift, the “Z” axis.
Rotate The Workspace
When you are working in a 3D world, it’s important to rotate your view often to make sure that things are where you think they should be. Because our screens are only 2D, you have to rotate the workspace in your 3D Design tool to make sure that all the surfaces are lining up.
For instance, in the workspace below, it appears as though the red cube and blue cube are perfectly lined up.
If I rotate the workspace, I can see that the blue cube is raised slightly on the Z axis and the bottoms do not line up. This is a very simple example but the more complex the design, the more likely that issues will arise from not rotating the view.
Bottom Up Design
How is designing for 3D Printing different from designing for 3D gaming?
A lot of the same tools that are used for designing objects 3D games, can also be used for designing objects for 3D printing but there are some things you need to consider before you bring one of these designs to life on a 3D printer.
In 3D game design, gravity can be turned off while an object is placed in the game world and then held in a certain spot. In Minecraft, you could create a floating platform because gravity is turned off for those blocks.
A 3D printer, on the other hand, can not turn off gravity. It starts by printing the bottom of the object and then slowly adds layers on top of the bottom layer to build up your object. A structure like the one in the Minecraft image above would not be possible unless we lowered it to the platform. The image above is an obvious (and un-useful) example but let us take a look at some other examples that may be less obvious and more likely to be 3D printed.
This creature would be very difficult to print because the overhang on the green wings would not have any supports.
Floating Object Check
It’s important when you are evaluating whether or not a design is actually ready for printing to check for floating objects in your design. You can easily do this by rotating the workspace and your design and examining from all angles.
This design looks great from the top down:
It even looks pretty good as you begin to rotate around to the side:
However, once you look at the side view, you can see that all of the letters are floating and not actually attached to the keychain base. If you were to print this design as is, the letters would not print and you would end up with a blank keychain.
This is the exact reason that we rotate the workspace and look at our designs from all angles before printing.
This video demonstrates what happens when you print an object with too much overhang and gravity takes over.
Here is what the design looks like on the screen: