Magnetic Chess Set

G. Tielke September 2022

V3: Revised to be scalable in size

Remix of:

OpenSCAD Chess Simple Printing
by Zarlor January 26, 2019
https://www.thingiverse.com/thing:3381939
(Which itself is a remix of https://www.thingiverse.com/thing:585218)

Note: Not recommended for households with small children in case the small magnets get loose and are swallowed.

Each piece holds a hidden magnet (10mm diameter x 2mm thick) so this works with magnetic boards, or boards with a metal layer of some kind. See my magnetic chessboard for example:

Chessboard - Magnetic Inlaid Style
G. Tielke, January 2021
https://www.thingiverse.com/thing:5165815

Each chess piece has a recess on the under-side, which a separate Base piece snaps into. Each Base piece holds a magnet. Be sure to install the magnets with the correct side up to work with your board.

Note: The Customizer will not work properly when run directly from the Thingiverse site. See the Customizer Notes below for more details.

I recommend that you glue each chess piece to its Base to ensure the magnet stays in place. Felt can also be glued to the bottom if desired.

I have included the SCAD file, so the chess pieces and Base parts can be customized if desired. The "dxf" files, and "horse.stl" and queen_crown.stl are used by the SCAD program.

Optionally, the Rook pieces can be printed with two-letter initials on the top.

Slicer settings using Cura:

Use 100% infill to give the pieces more heft.

No supports needed for any parts. I used a speed of 50 mm/s.

Pieces: Use a Raft.
For the Knight pieces, use a high resolution (0.12mm layers).
The Knight pieces print with extra parts that snap off.

Bases: No raft. These hold the magnets and snap onto the bottom of each chess piece. Bases come in two sizes:

Small - for Pawns
Large - for all other pieces

NOTES:

The default size has a base diameter of about 25mm (one inch), and King height of about 50mm.
-Scalable, from 50% to 200% in height and/or width.
-Choose how many of each piece to create.
-Optional separate circular base pieces:
These glue onto the bottom of the pieces to hold a magnet.
-May add a weight (coin, washer, nut, etc.) by specifying the diameter and width of the hole underneath. Or attach felt to the piece or to the base part.
-Can add initials (up to 2 characters) to Rook pieces.

For the flat Base pieces, the small size is for Pawns, and the large size is for the other pieces.

Each set should be printed twice in two different colors (traditionally in Black and in White).
-Use 100% infill for more weight to the pieces.
-No raft or supports should be needed.
-I used layer height=0.2mm, speed=50mm/s. Smaller values may provide better quality.

Removable supports are added to the Knight piece to make it printable. The supports snap off after printing.

You probably do NOT want to print all pieces in one run; it will take a long time (and may will not fit on your printer platform).

CUSTOMIZER NOTES:

The Customizer button on the Thingiverse page will not work properly, because of the need to have access to the ".dxf" files. You will need to download all of the files and run the OpenSCAD program directly on your computer.

REQUIREMENTS:

The "OpenSCAD" file requires the installation of OpenSCAD, free software available here: https://openscad.org/

Several ".dxf" files and ".sql" files need to be downloaded and saved in the same folder that the ".scad" file is saved in:

 king_profile.dxf cross_profile.dxf (cross on top of the King piece) queen_profile.dxf bishop_profile.dxf rook_profile.dxf pawn_profile.dxf knight_profile.dxf (pedestal only for holding the horse head)     horse.stl (for the horse head shape of the Knight) queen_crown.stl (crown on top of the Queen piece)

After using OpenSCAD to create an STL file, use any slicer program to create a file for your 3D printer. I use the CURA slicer program available here:
https://ultimaker.com/software/ultimaker-cura
(free even if you do not own their brand of printer)

ADVANCED:

To make further refinements to the chess pieces:

The .dxf files may be edited using LibreCAD, free software available here: https://librecad.org/

The .stl files may be edited with any of several programs. I use Tinkercad, free software available here:
https://www.tinkercad.com/