This design is for 3D-printed iambic paddles for sending Morse code. The design is simple, but provides precise movement with adjustable force and travel. Design features include printed rocker hinges, force adjustment by a sliding spring, travel adjustment using a modified screw, ergonomic grip and general simplicity and precision. The design is compact and well suited for portable use. The design can be tuned or modified by changing the OpenSCAD code, for example to change the paddle shape to your taste (but consider trying the somewhat unusual default shape first). Assembly instructions are given in a separate document.
This design lives on GitHub here: https://github.com/tskauli/MorsePaddles