This is a remix of AMAZINGSPANOMAN's customizable fidget spinner ring but I've enlarged it a good bit and added a broader top to it in order to show the Circle of Fifths from music theory. I've added the I, III, IV and VII to the spinner so that the if you understand the circle of fifths then you an use this to find the notes in a chord. I printed it in white PLA and used a sharpie to color natural or sharp noted black and flat notes red. For more on the circle of fifths, see google.
3D design, CNC, Laser Cutting, Plotting, Electronics, Software dev, Learning Bluegrass Mandolin & Bass, Design and build CNC devices (pen plotters, welders)