Where do weird unwanted UVs come from?

It’s not the first time I notice some UVs in my list which I’m sure I never made. Where may they come from?
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Hi there,

Some addons, e.g. baking or UV packers may create separate UV maps for their doings. Maybe you ran into that?

Otherwise, if you don’t need them, you can simply delete them :grin:

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merging different objects with different uv names

Are those imported objects? Cuz as far as i remember “uvchannel_#” is 3ds max specific name, and “map#” is maya’s.

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Personally, I’d be very reluctant to delete them. They’re probably not doing any harm, and you really don’t know what they might be doing. You might sorely regret having deleted them.

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Well… you can look at them and maybe see something… even delete them and try a test render… blender is no black magic… so why so anxious ?? And if there are some different UV’s used to make some interesting tricks… you should know about that (even if using an addon)… :person_shrugging:

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It can happen when you join multiple objects whose UV maps all have different names, even if each object only had 1 UV map.

You can find out what faces those other UV maps are influencing.
Select each UV map to see what faces show up in the UV editor. If you want to combine them all into one map, do this: (as mentioned above, before proceeding it’s best to check if any addons are using those UV maps for something, or if you need them for texture baking)
In the UV editor press the Synch button so that the selection in the UV window matches the selection in the 3D view:

For each UV map select all the faces, then separate them to make a new mesh (P in the 3D view, requires that Synch button)

In your example you’d then have 3 meshes, all with 3 UV maps, but each only needing 1. For each mesh it’s up to you to carefully delete the 2 UV maps they don’t need. For each mesh, rename it’s remaing UV map so it’s the same for all 3 meshes. You can then join them again, if necessary.

I know that I can, I was just curious where they came from, because I haven’t noticed them at first and they screwed texture mapping when import to UE4

Thanks, this must be it!

Deleting them didn`t do any harm after all, it seems they were just some leftovers from other 3d soft

These names are usually found on imported models. So those are the original UVmaps on the models you’ve imported from other software.