Can you spot the one I made at TechShop?
A missing game piece is the worst! Waiting for a replacement to be delivered or finding where your pet hid it can be time-consuming. Wouldn't you rather get back to playing?
Missing game pieces are a great use for 3D printers and a good way to learn 3D design, because the shapes are simple. In this instructable, I'll demonstrate the workflow involved in 3D design while making a replacement Sanctuary piece for Terra Mystica.
Step 1: Tools and Safety
Electronic Calipers are the only tool I used for this project. They are available for about $20 online or in a hardware store. The can be used to measure outside width, gap width, or depth.
Other tools that are useful for more complicated projects are the digital protractor (also about $20) and a laser range finder. The Bosch model is a little pricey at $89 -- but it can measure from the end of the probe, from its base, or from its top. This is useful when measuring the exact inside dimensions of gap that is inside the build volume of your 3D printer.
A 3D Printer. I use the ones at TechShop, but printers are available at your local makerspace, school, or hardware store. Make: magazine publishes An Ultimate Guide to 3D Printing each year that compares and reviews all the models available at the end of each year.
Printer filament. It should be the correct color and type for the printer you're using.
The calipers and protractor have pointy/sharp parts. The laser range finder is not eye-safe. 3D printers are about as dangerous as a coffee maker, but read the manual and/or take a class to learn how to use one safely. The hot end of a 3D printer gets up to about 200 degrees Celsius.
Step 2: Measure
Use calipers to measure the dimensions of the piece you are reproducing. If what you're measuring isn't portable, you can store its dimensions in a measuring/sketching app. In this case, it is easiest to measure while at the computer.
Step 3: Draw the 2D Shape
I used Autodesk 123D because it is available for free. I mostly design in Autodesk Inventor because it is a bit more powerful, and it comes as a perk with a TechShop membership.
A way to explain the process of 3D design is to draw your 2D shape, dimension it correctly, and then extrude it into the third dimension. Since this is a simple shape, we'll only have to do that process once.
With more complicated designs, you'll do one of two things: either draw new shapes on one of the faces of your object and extrude them from there, or create a new shape and add it to your first one.
Step 4: Extrude the 2D Shape Into 3D
Once you're satisfied with the 2D shape, extrude it the distance that you measured earlier.
That's it for the 3D design! Export the shape as a .stl file and name it.
Step 5: Slice the .stl File
A slicer converts an .stl file into instructions that a 3D printer will use. The file exported from a slicer will tell the printer where, when, and how fast to move the print head, and when to start and stop extruding plastic.
There are many slicers available. The Dremel Idea Maker (pictured) and MakerBot provide slicers already configured for their printers. Autodesk's Meshmixer is integrated with 123D Design and supports many printers. Some manufacturers provide profiles that you can load into open source slicers, like Cura or Slic3r.
Follow the instructions to turn on the printer, ensure the print bed is level, load the correct color of filament, send the job to the printer, and then watch it go! An object this size will take about 10 minutes.
Step 6: Check Your Work
Looks good! They even weigh about the same.
A close look at the piece shows the lines of plastic that the 3D printer drew to create it. They can be sanded off with very fine sandpaper or smoothed using acetone.
Step 7: Share Your Design
There are many places online where you can upload pictures and your .stl file for other people to use.
Follow this link for the file from this Instructable hosted by Autodesk with other, better 123D files from other users. I also uploaded it to Thingiverse.