Maya provides several features for separating, merging, and attaching UVs. These features can be particularly useful when working with UVs that were generated using the Automatic Mapping feature.
| To... | Do this | 
|---|---|
| Separate a UV shell along the selected edges. | Select Edit UVs > Cut UV Edges. 
 | 
| Attach UV shells along the selected edges. | Select Edit UVs > Sew UV Edges. 
 | 
| Attach UV shells along the selected edges and move the shells together. | Select 
                                 Edit UVs > Move and Sew UV Edges >   
 | 
| Merge the selected UVs. | Select Edit UVs > Merge UVs. Merge UVs only merges the UVs that share the same vertex. You can specify an option for the maximum distance Maya will move UVs to merge them. | 
| Automatically attach and move small shells. | Select all the shells
                        and choose 
                                 Edit UVs > Move and Sew UV Edges >   Turn on Limit Shell Size and set the maximum size (in number of faces) for UV shells. Shells larger than this number will not move. Click Apply. | 
After performing a Move and Sew UV Edges operation, you can select the node (polyMapSewMove) and edit it in the Attribute Editor or Channel Box to adjust the Number Faces.