Spinning top / gyro (陀螺)

陀螺 is an inexpensive wood toy that we grew up with and there're similar spinning tops all over the world. I can't buy one here, so I want to build one for my kids to learn. My initial build was too big/fragile, so I redesigned a smaller one(https://youtu.be/BSIfdugXvtA) and with no sound holes. Since this is a 3D printed object and the high impact to the ground will likely to break it easily, I found the duct tape is a perfect remedy for that and recommend to cover it before your first shot. Total print time is about 10+ hours with 0.24 layer height.

Even though the original screw holes are designed with M6 0.8, but it fits M5 0.8 nicely due to the print tolerance. I made another one(filename with a M6 at the end) with M7 1, so that it can fit with M6 1 bolts. If you use a drill bit to clean up the holes or you have a perfect print machine, you can fit M6 0.8 or M7 1 bolts. The M6/7 bolts are better/stronger and provide more weight. The M5 spinning tip is weaker and can actually ben