Core Mechanics

There are a few primary mechanics you need to learn about to master subdiv modeling. They all feed into each other and it can be a bit of a mind warp to try and think about them all the time, but the good news is you don't need to. They only matter when trying to problem solve or plan approaches to complex curvature.

The best way I can explain subdiv is by thinking of edges as rubber bands tied to movable pegs (verts) and they are all trying to equalize themselves. The longer ones pull harder, and the more edges around the pole that are the same or similar length, the more stable that pole is. So say you have 5 edges on a pole where 4 of them are the same length. If the 5th one is longer, the vert is going to only move along that long edge because the others are pulling with equal strength.

in order to work with poles on curves, you focus on the primary curvature goal, identify which edge you need the vert to move along the most to not upset the curvature, and which edges should be used to stabilize. If you need the pole to not move at all, you need to focus on using equal edge lengths.