Trying to make a Spiral Material on a Ball but not going how I hoped. The Red & White is twisting the geometry and the Black & White is a Material as can be seen it’s not right. How can I fix this? …
First, it’s not necessarily going to match up to UV. What you UV does depends on what your UV is. You can map UV to various values if you want. (But doing a 3D spiral is something you want to do in 3D coords, so your best bet is to use object coords and then, if needed, bake to a texture.)
Second, the tutorial you’re using uses a gradient texture to get the “length”, which means it’s clamped in 0 to 1 range. You can see that at the borders of the plane, where it stops working when the distance from the center of the plane gets larger than 1-- it’s drawing a circle on your plane. You don’t have to get the length like this, you can just use plain old fashioned length if you want.
You can use either length or Z axis to drive the spiral, or mix the two; you end up with different kinds of spirals, depending in part on your geometry.