Sew UV Tool

To open the Sew UV Tool, select it in the Cut & Sew section of the UV Toolkit or select Tools > Sew from the UV Editor menus. For more information on sewing edges, see Separate and attach UVs

The Sew UV Tool lets you weld UVs by dragging along edges. Press Ctrl to temporarily activate the Cut UV Tool. Maya will respect UVs current pinning status during sewing (i.e. pinned UVs will only be sewn if they can do so without moving, while unpinned UVs will move together to be sewn).

The following options appear in the Tool Settings window when you select Tools > Sew > .

Brush

Size
Specifies the radius of the tool. Any split edges that are within the radius when you drag your cursor across a shell are merged together.
Steady Stroke
Helps to produce a smoother stroke by filtering mouse movement. When on, a vector displays on the tool cursor and edges are not joined together until you drag a distance equal to the length of the vector. The length of the vector is set by the Distance setting.
Distance
Sets the length of the Steady Stroke vector on the tool cursor.
Display All Shell Borders
When on, highlights shell borders. Sets of connected edges are displayed in different colors, making it easy to identify edges that are shared. Display All Shell Borders is off by default.