Q:

How to make such cogwheel in 2.82?

I am watching a video for tank track, and now i have reached to the drive wheel. It needs to have pointy surface in order to move the tracks. The guy in the video made a circle, selected all vertices and then used "Checker Deselect" to select vertex, then skip one and so on. Then he scaled it down, making something like a sun. But when i try to scale, it doesnt even move. I tried with move and rotate, i tried to extrude, but still no result. Does anyone know how can i do this?

A:

But when i try to scale, it doesnt even move.

You can scale with the scale tool - press and release alt and then s, or select in the tool panel:

Or you can just hit s to use interactive scale operator.
You should also make sure you have the correct selection and that you are using the transform pivot that you want, that you can select here:

