Snap-Block snappable toys. The block receives frames containing letters, numbers, or any image you can apply to the STL! Use these blocks to help kids associate words with images, to practice spelling, or even for multi-sided puzzles. There is not really a commercial equivalent for these since they are easily customizable and interchangeable. Similar size and textured alphabet blocks are available on etsy for $48 (26 blocks), but these are single-letter, single sided, and do not allow images. At 20% infill using Hatchbox PLA filament, the same number of blocks can be printed for around $30, with all the added functionality of color, letter/number, and image interchangeability.
The OpenSCAD file is designed to be a customizer - download snap_frame.scad, enter a letter, and output an STL.
To apply an image, such as the ship used in the example, import snap_frame.stl into a 3D modeling software (I recommend Blender) and extrude the image inside the frame. To get any picture into Blender, follow the directions here.
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