A guide to unit management in SimSolid.

SimSolid automatically manages Units consistency throughout the application. You are free to mix and match any unit values at any time. Units are commonly given in either metric (SI) or imperial (IPS) systems. Units are defined in several application areas.

Geometry Import

Model length units are set at the time of geometry import. Once defined they cannot be altered. For Onshape and SolidWorks documents, embedded model units are used. Since STL files are by definition unitless, a dialog will prompt for guidance (millimeter, centimeter, meter, inch or foot). Bounding box dimensions are displayed to aid the user in selecting the appropriate value.

Default Units

Default units will be used throughout the application and can be set for the current session only or for all sessions. You can set separate defaults for both input and output unit displays. Defaults are set to either metric or imperial. Additional defaults may be set for individual quantity types. For example, in IPS units, stress values can be set to PSI or KSI.

Three types of numerical output formatting are available, and with each a number of significant digits can be specified:
  • Scientific (example: 1.2345e+3)
  • Engineering (example: 1234)
  • Concise Mix (This will attempt to use Engineering format but switch to Scientific when the scale is too small.

Material Definition

Materials can be created in either IPS or SI format on the Material Database dialog. Units will be managed internally. So, a SI defined material may be used in a model using IPS values and vice versa.


The default input units are displayed on all load and constraint definition dialogs. You can specify alternative units during load/constraint definition or editing.

Output Units

The default output units are displayed on the contour legend. These output units may be overridden (for the current plot only) by the Change units button on the legend control dialog.