UV unwrap not working?

Question

I'm trying to linearly unwrap a wheel into 4 lines. So I select the 1st 1/4 faces, U->Follow Active Quads, and the unwrap shows up in the UV editor. Then I select the next 1/4 of faces, U->Follow Active Quads... nothing happens. Try another set of faces. Same thing.

Why can I unwrap any more faces?

None of the suggested answers helped. The point of this question is that nothing happens when I hit unwrap. Nothing shows up in the UV editor.

https://blender.stackexchange.com/questions/78358/how-to-straighten-curved-uvs-into-straight-belt/ and https://blender.stackexchange.com/questions/92812/how-can-i-assign-the-texture-on-saturns-rings/ or https://blender.stackexchange.com/questions/74041/how-to-perfectly-align-uv-coordinates-automatically/ — Duarte Farrajota Ramos, Apr 15 '18 at 17:37
Possible duplicate of How to perfectly align UV coordinates automatically? — Duarte Farrajota Ramos, Apr 15 '18 at 17:37
Follow Active Quads must be provided with an active quad already unwrapped (as is already shown in linked answers). Otherwise its unwrapping effect won't be apparent — Mr Zak, Apr 18 '18 at 20:00
So do the UVs show in the UV Image editor or not? what exactly does "nothing happens" mean? — David, Apr 19 '18 at 00:31

aliasguru · Accepted Answer · 2018-04-18T19:42:08.887

I wasn't aware of this behavior myself so far to be honest, but I was able to replicate what you described on a simple cylinder with a few loop cuts on the side. The first face ring would unwrap no problem, but all the others would fail. At least the command seems to do nothing.

Here's a small video demonstrating the behavior:

In fact, it does perform an unwrap, but it is scaling all resulting UVs to zero.

To fix it, perform any other unwrap on the whole mesh before you start the Follow Active Quads method. For example, use Smart UV project. Afterwards, you can unwrap ring by ring.

Of course, it is also possible to unwrap more than one ring at once:

UV unwrap not working?

1 Answers1