Solid Modeling - Good Practices Part 2

[ndcadadmin]

Source:
Multiple Authors.

Solid Modeling is a Science
The rules of productive Solid Modeling are primarily based on underlying mathematics. Fortunately, being a mathematician is not a prerequisite to being productive. When well understood, it becomes clear that Solid Modeling is a science, and not a mysterious and obscure art. - Dr. Richard Lowrey, Mechanical Engineering Consultant

Geometry Alignment
Use aligned construction geometry (that which is pre-aligned, touching, and sharing common vertices, edges, etc.) to create features on a solid model for a more robust mathematical representation. - Scott McOlash, Engineer

A System's Dynamic Range
A Solid Modeling system has a dynamic range and may have a finite number small verses large feature entities in the model simultaneously. Some may have limited solver capabilities to handle many multiple referenced datums or parametric features. When the dynamic range is exceeded, not one additional feature can be created without a problem. - John Skibinski, Program Director

ID Checks
Watch out for the integrity of your entities (objects) after you perform boolean operations. A worthwhile CAD program will have some sort of ID (Identification) command where you can grab on to an object to find out information about it. It doesn't hurt to ID your objects after boolean operations so you don't build more complex things on top of a faulty foundation. - Keith Campbell, Engineer, VP Marketing

Testing Intersections
Surface intersections can be trial viewed by shading the non- intersected geometry. Faceted displays may need to use finer polygons and/or smooth shading for this technique to be most
useful. If positioning is incorrect, the intersection and subsequent editing time is avoided. - Dr. Richard Lowrey, Mechanical Engineering Consultant

Do Not Display Unused Geometry
To speed redisplay, make all unnecessary geometry and constructions invisible. Finding the ideal orientation for current operations can be less time consuming. - Dr. Richard Lowrey, Mechanical Engineering Consultant

Adding Surface Regions
Some Solid Modeling systems may not allow for creating surface regions on continuous surfaces. Designers may need to create a surface region to ease the use of the solid model in other applications.
For example, a pressure may reside on a portion of a surface. Or a concentrated force may be applied to a small region of a surface. For analysis accuracy, the finite elements generated should not cross the boundary of the region, and the finite element analysis software may not allow for applying the pressure to a region of the complete surface. Hence, the finite element analyst may desire the surface broken into regions via edges while the NC programmer needs the surfaces continuous. - Dr. Richard Lowrey, Mechanical Engineering Consultant