This is one of a series of educational displays I made for the Arcade Library in Sacramento to help teach people about 3D printing.
It can be difficult to explain important 3D printing concepts like printing with supports, the effect of the number of shells, resolution, infill percentage and using a raft.
Sometimes all you need is a good visual aid to make things click.
This is a shell display that shows the effect of different "number of shells" settings. A one inch cube is printed ten times with various settings. Cubes with 1-5 shells are on one row and then 10, 15, 20, 25, and 30 shells are on the next row. It is easy to see how the number of shells effects the stability of a print and the translucency.
There is enough space between the cubes to squeeze them to feel how flexible or ridged they are.
It's a great way to quickly find out how many shells you should use for your project.
See the instructions for details on how to make this display for your classroom or wherever else it is useful.
You will need to print the file "25mm cube.stl" ten times.
Print times get longer as you print the cube with more shells, the longest print was 40-50 minutes
Print each cube with 0% infill and 0.3mm layer height.
Print the first cube with 1 shell. Before the print finishes, cancel the print. Do this before the printer seals the top of the cube and you can't see inside of it.
EDIT: It has been brought to my attention that there is a setting called "top layer height" in the advanced settings of MakerWare and Cura. Setting this to 0 will print the block without the top automatically, so you won't need to cancel the print at the end to leave it open so you can see the inside.
When I printed these cubes I put the first cube next to the cube that I was printing near the end of the print, and then canceled the print when it was approximately the same height.
Print the 2nd thru 5th cubes each with 2, 3, 4, 5 shells, 0% infill and 0.3mm layer height.
Do the same with 5 more cubes with the shell settings: 10, 15, 20, 25 and 30 shells.
The next step is printing "Display Row 1-5.stl" and "Display Row 10-30.stl"
I used the settings 5% infill and 2 shells and 0.3mm layer height.
Pick two colors, one for the letters one for the background. Load the filament of your choice for the background and start the print, when the printer starts to print the first layer of the letters and is done with the rest of the model go to "change filament" in the menu of your 3D printer. Then proceed to unload filament you were printing with and load the filament you have chosen for the letters. Then continue the print. Do these steps for both files. I would not recommend printing both files at once in case you make a mistake and have to start over.
Do the same steps for "Number of Shells Display Label.stl" that goes on the front of the display.
Last print the "display steps.stl" file in the color filament of your choosing.
The settings I used were 0.3mm layer height, 2 shells and 5% infill.
Now glue everything together. I glued the cubes down to the display so they do not get lost.
The glue I used is "Model & Hobby Cement" from the dollar store. It's strong but not so strong that you cannot get it apart if you make a mistake.
Enjoy! Teach and spread the knowledge of 3D printing!