-- gen-2-fidget-spinner.stl is the file imported from tinkercad and contains all components. I heavily recommend not printing this file, because the different components have different printing requirements.
-- If you would like to use the printable ball bearing, print it first. Be sure to remove any "elephant footing" that may have ocurred, and free the bearing center by rotating it or running a craft knife in the gap between the center and the outside if it is stuck. For a longer spin time, print it with IGUS iglidur l180-PF Tribo-Filament (available at http://www.matterhackers.com/store/3d-printer-filament/igus-iglidur-l180-pf-tribo-filament-1.75mm).
-- Print the endcaps in your usual settings; if it does not fit, sand down the peg to make it fit.
-- When slicing the spinner body, insert pauses at heights 7.6mm and 9.4mm. Insert 4 pennies into each of the side compartments at 7.6mm, and insert a 608 or Gen2 printed ball bearing into the center at 9.4 mm.
-- To create a tricolored spinner, switch filament colors every 33% of the print.
-- Print at optimal bridging settings for your machine, 0.2mm layer hieght and 35mm/s is a good start.