I designed this using an equation in cylindrical coordinates. You can print in vase mode or also make it solid since I designed it to have about 1.5mm walls. When you first load into your slicer you'll need to scale up 2560% since the thing exports as mm for some reason. I get better results by printing slowly at 30mm/s
If you're a math teacher you can annoy your students by making them figure out the volume of it, the z value starts at zero and goes to 2pi
spiral_cup.stl | 7.9MB |