This 20-piece earth puzzle will test your geography knowledge!
The puzzle is based on a 20 sided icosahedron. Each edge has holes for a pair of 3mm x 1mm cylindrical magnets to hold it all together.
The files are grouped in to "N," "NE," "S," and "SE." Each group contains five puzzle pieces. Pieces labeled "N" share a vertex that lays roughly at the north pole near the Bering Strait. "NE" pieces all share an edge with an "N" piece. Pieces labeled "S" share a vertex near the south pole. "SE" pieces all share an edge with an "S" piece.
There are separate files for each piece, as well as "Combined" files to print groups out together. Printing the "Combined" files is the best way to go. The "Full Earth Print Ready" has all the pieces together, but this is risky in that an error part way through the print will ruin the whole thing.
If you choose to scale the files, keep in mind that the holes designed for 3mm x 1mm cylindrical magnets will no longer be the appropriate size.
Printing this with layer heights of .15 mm or greater results in visible contour lines in the oceans that can be distracting to the overall design. I recommend printing with a layer height of .10 mm or less.
This project can also be made out of wood: https://www.thingiverse.com/thing:4160023 or with interlocking pieces instead of magnets: https://www.thingiverse.com/thing:4153522
Post-Printing
The model displayed was printed with blue filament. Land masses are painted green, the poles are painted white.
The holes for the 3mm x 1mm cylindrical magnets often print with small burrs inside, so it is a good idea to clean them out with a 1/8 inch drill bit before inserting the magnets.
It is important to pay attention to magnet polarity or the pieces won't snap together! The pair of magnets on each edge are inserted with opposite polarity. Maintain the same pattern around each edge and across each piece. Use dab of CA glue to hold the magnets in place.
