I've historically been exclusively (other than obvious parts like hardware) using laser-cut acrylic for all of the clock components, but now that 3D Printing has matured to the point where any dummy like me can walk into a store and walk out with a functioning 3D printer, I've joined the club. I was hesitant at first, since just creating digital models can be a daunting endeavor, if one starts to look at CAD software, slicers, modelers, etc.
However, with the popularity of 3D printing, a few things have popped up that make life pretty easy for those just starting out. TinkerCAD is a pretty basic, but still powerful way to create either simple or relatively complex objects by combining and mixing simple shapes and holes.
Even with the basic and free tools available, I'm now using a few printed parts here and there, but only in non-cosmetic locations, like the Sprocket Mount shown below. Check it out!