Command entry:Create or select an object. 
Quad menu Transform quadrant Convert To: submenu Editable Mesh
Editable Mesh, like the Edit Mesh modifier, provides controls for manipulating a mesh object made up of triangular faces as an object and at three sub-object levels: vertex, edge and face. You can convert most objects in 3ds Max to editable meshes, but for open spline objects, only vertices are available, because open splines have no faces or edges when converted to meshes.
To make a sub-object selection on a non-editable mesh object (for example, a primitive) for passing up the stack to a modifier, use the Mesh Select modifier.
Once you make a selection with Editable Mesh, you have these options:
To produce an editable mesh object:
First select the object, and then do one of the following:
Use the Collapse utility.
Import Merge.
Converting an object to an editable mesh removes all parametric controls, including the creation parameters. For example, you can no longer increase the number of segments in a box, slice a circular primitive, or change the number of sides on a cylinder. Any modifiers you apply to an object are collapsed as well. After conversion, the only entry left on the stack is "Editable Mesh."
Maintaining an object's creation parameters:
As described in the above procedure, you can convert an existing object to an editable mesh, which replaces the creation parameters in the stack with "Editable Mesh." The creation parameters are no longer accessible or animatable. If you want to maintain the creation parameters, you can use the following modifiers:
Normally, if you apply a modifier such as Twist to an editable-mesh object and then return to the Editable Mesh stack entry, you cannot see the effect of the modifier on the object's geometry. But if you turn on Show End Result while in sub-object level, you can see the original sub-object selection as a yellow mesh, the final object as a white mesh, and the original editable mesh as an orange mesh.
At the bottom of the Selection rollout is a text display giving information about the current selection. If no objects or more than one sub-object are selected, the text gives the number of objects and the type selected. If a single sub-object is selected, the text gives its identification number and type.
Soft Selection controls affect the action of sub-object Move, Rotate, and Scale functions. When these are on, 3ds Max applies a spline curve deformation to unselected vertices surrounding the transformed selected sub-object. This provides a magnet-like effect with a sphere of influence around the transformation.
For more information, see Soft Selection Rollout.
The Edit Geometry rollout provides various controls for editing an editable mesh object and its sub-objects. For information specific to the different sub-object levels, see the topics in this section.
The Selection rollout provides tools for accessing different sub-object levels, working with named selections and normals, display settings, and shows information about selected entities.
Editable Mesh (Object) controls are available when no sub-object levels are active. These controls are also available at all sub-object levels, and work the same at each level, except as noted in Edit Geometry Rollout (Mesh).
Vertices are points in space: they define the structure of faces. When vertices are moved or edited, the faces they form are affected as well. Vertices can also exist independently; such isolated vertices can be used to construct faces but are otherwise invisible when rendering.
An edge is a line, visible or invisible, forming the side of a face and connecting two vertices. Two faces can share a single edge.
A face is the smallest possible mesh object: a triangle formed by three vertices. Faces provide the renderable surface of an object. While a vertex can exist as an isolated point in space, a face cannot exist without vertices.
The Edit Geometry rollout for Meshes contains most of the controls that let you alter the geometry of the mesh, at either the Object (top) level, or one of the sub-object levels. The controls that the rollout displays can vary, depending on which level is active; if a control is not available for the active level, it might be grayed out, or simply might not appear at all. The descriptions below indicate the levels at which controls are available.
The Attach Options dialog opens when you attach two or more objects to which different materials are assigned. It provides three different methods of combining the sub-materials and the material IDs in the two objects.
The tools available in the Cut And Slice group let you subdivide edges and faces to create new vertices, edges, and faces. You can slice an editable mesh object at any sub-object level; the Cut tool is available at every sub-object level except Vertex.
Modify panel