Requirements

Blender 4.2 or newer (developed and tested on 5.1).

Installation

1. Download simple_reset_align-x.y.z.zip. Don't unzip it.
2. In Blender, open Edit > Preferences > Get Extensions, click the drop-down arrow at the top right and choose Install from Disk…. You can also drag the zip into the Blender window.
3. In the 3D viewport, press N and open the Reset Align tab.

Use

1. Select one or more meshes. In Edit Mode, you can select the faces, edges or vertices that should line up instead.
2. Press Preview to see the angle, then Align.
3. The same command is in Object > Transform and Mesh > Transform as Reset Align. Press F9 afterwards to change options and redo.

Options

• Reference: Auto uses your Edit Mode selection, else the largest flat area, else PCA. Selection, Largest Flat Area or Thin Axis (PCA) force one method.
• Target Axis: Nearest Axis, X/Y/Z (either sign), or +X/-X/+Y/-Y/+Z/-Z.
• Pivot: Median of Geometry, Object Origin or 3D Cursor.
• Square Up Edges: also spin the mesh around the target axis so straight edges line up. Turn it off to align only one direction.
• Origin to Geometry: move the origin to the mesh centre afterwards.
• All Selected Objects: align every selected mesh, or only the active one.
• Make Single User: give shared mesh data its own copy instead of skipping it.