Expand/Contract solid

You can use this function to expand or contract a solid by a set distance. You can use this function to create a dilution skin around an ore solid. You can also use the slight smoothing effect of this function to remove small geometric irregularities in Cavity Monitoring System (CMS) solids.

To run this function: Choose Solids > Mesh tools > Expand/Contract, or...

In the Function Chooser, type MESH SOLIDS EXPAND, and press ENTER.

To run this function: Choose Solids > Mesh tools > Expand/Contract.

Fields on the Expand/Contract solids form

Field	Description
Selected objects
Active layer	Display only. The current active layer that contains the solid.
Object Range	The objects that you want to expand. If you leave this field blank, all objects in the active layer are expanded or contracted.
Trisolation Range	The trisolations of the object that you want to expand. If you leave this field blank, all trisolations in the active layer are expanded or contracted.
Select button	Allows you to select the objects and trisolations that you want to expand or contract in Graphics.
Settings
Expansion distance	The value by which you want to expand or contract the solid. Positive values expand the solid. Negative values contract the solid.
Precision	The degree of accuracy between the shape of the solid being expanded or contracted and the new solid. The more precise the expansion or contraction, the greater the number of triangles in the new solid. Note: The higher the precision, the more time and memory is used for the expansion.
Output
Overwrite existing objects	The expanded or contracted solid replaces the original solid in the layer.
New layer	The expanded or contracted solid is created in a new layer. If you select this option, you must type a name for the new layer.
Simplify results	Selected: The number of triangles in the new solid is reduced. The position of the slider determines the degree to which the triangle number is reduced. Min removes the least triangles, Max removes the most triangles. Cleared: The number of triangles in the solid is not reduced.

Output

The expanded, or contracted, solid is displayed either in the current layer, or in a new layer.

Troubleshooting

Solids with triangles that face inwards can cause undesirable results when they are expanded or contracted. To avoid this problem, use valid solids, in which all of the triangles face outward.

The precision value that best suits an expansion or contraction depends on the nature of the solid you are modifying. For example, thick solids give a better result with a different precision value to thin solids. To get a good result, start with the default precision value. If the solid created is too blocky, contains holes, or you are not happy with its shape, increase the precision value. If you are satisfied with the shape but the new solid contains too many triangles, decrease the precision value.