The option to flip or invert faces  is an Edit Mode option only (accessible only when editing meshes), click Mesh » Normals » Flip [2 & 3] with an individual face or group selected.
How do you flip an object in Blender?
To flip an object on an axis, select the mesh, press s for scaling, and then press the axis you want to flip on (x, y, z). Type -1 to flip.
How do you flip vertices in blender?
To access the option and/or correct an inverted or inside-out face, first select the errant mesh element in the 3D View (Edit Mode selection) then from the Mesh menu click Normals then Flip Normals from the options that appear – Mesh » Normals » Flip Normals.
How do you mirror a mesh blender?
After this tool becomes active, select an axis to mirror the selection by pressing X , Y , or Z . You can also interactively mirror the geometry by holding the MMB and dragging in the desired mirror direction.
How do you make something symmetrical in blender?
The Symmetrize tool is a quick way to make a mesh symmetrical. Symmetrize works by cutting the mesh at the pivot point of the object, and mirroring over the geometry in the specified axis, and merges the two halves together (if they are connected).
|Menu:||Mesh ‣ Symmetrize|
How do I join two objects in blender?
- Select both objects in object mode. Press Ctrl+J to join the objects into one. Then enter edit mode and change to face manipulation mode.
- Remove the faces that will be joined. Select them and press X , remember to delete faces, not vertices.
How do you Unjoin an object in Blender?
How to Unjoin Two Items in Blender
- Press the “Tab” key to enter Edit Mode.
- Right-click on the vertices that connects to two items to select them. You can also press the “Ctrl+L” keys to select all linked vertices.
- Press the “P” key.
- Click “Selected” from the menu when prompted. Blender will unjoin the two connected items.
How do you turn on backface culling blender?
To enable or disable, select the object for which backfaces are to be culled then in Material properties scroll down to the Settings options and click the Backface Culling checkbox.
How do you merge vertices in blender?
To merge elements together, first make a vertex, edge or face based selection then from the Mesh menu click Merge (Mesh » Merge) – alternatively press the M key.