I'm new here but after a recent break of a brand new piece of glass, I want to design a new one and get it custom made. I have two things that I want for this design: I want the glass to be strong enough that just tipping it over won't break any part of it and I want a light slow suck at the top to pull very strongly on the bowl. For the first part, I have a reasonable idea of how to do what I want. You would find the center of mass and the amount of force required to tip it over using torque. From there somehow calculate the velocity that it reaches in the fall and calculate the force on it. They I would find the force necessary to break glass in terms of thickness and basically use this to determine the thickness of glass I want. I do know that the thickness of the glass effects the center of mass and thus the force to tip. The other thing I want to know is how the force travels through the glass. For anyone that has no experience in the waterpipe field, it's fairly common for one to be knocked over and while the outside doesn't break, the percs (small glass tubes that are inside of the main tube) often break off. The second thing I want to try to design it in a way where the smoke will build up in the tube, aka milking. It is very obvious that some pipes do this better than others but I can't seem to figure out the physics behind it. I don't understand the physics that allows this to happen and all I know is that it's related to the pressure differentials between the different percs and the density of the smoke.