CADDIT CAD CAM CNC Software - download AutoCAD compatible design software progeCAD Alibre T-FLEX and more
CADDIT Website Knowledge Base Search:

progeCAD Help

Welcome to progeCAD
Working with progeCAD
Command Reference
CAD System Variables
Programming progeCAD
Full Index (caution - 400kb)

Further Links:

Download progeCAD
Register progeCAD


T-FLEX PLM tutorial (PDF)
progeCAD IntelliCAD and AutoCAD training 
CATIA 2D 3D design tutorial
Alibre CAD/CAM basic tutorial


Educational CAD Software Solutions
Python scripting for DOS and Windows
Other free software downloads
CADDIT CAD CAM Forum Australia

Coons Surface

Toolbar: Draw 3D > Coons Surface ()

Menu: Insert > 3D Entities > Coons Surface

Keyboard: EDGESURF

Experience Level: Advanced

Creates a three-dimensional mesh with vertices averaged between four edges.

You can apply this command to any four adjoining edges. The edges can be lines, arcs, or open two-dimensional or three-dimensional polylines, but all edges must be touching to form a closed, rectangular entity. You can use the SURFTAB2 system variable to define the N-direction mesh density of the coons surface.



  1. Select the first edge for the mesh.
  2. Select the second edge.
  3. Select the third edge.
  4. Select the fourth edge.

Before you can use the Coons Surface command, you must draw four connected linear segments.

Select the first of four connected linear entities for edge surface: You can select the four edges in any order. Select the first edge. The first edge you select determines the M-direction of the mesh, extending from the endpoint closest to the point you selected to the other endpoint. The two edges that touch the first edge you select form the N-edges of the mesh.

Select second edge: Select the second edge.

Select third edge: Select the third edge.

Select last edge: Select the fourth edge.

NOTE You can change the M- and N-surface densities with the system variables SURFTAB2, respectively. The minimum value is 2; the default is 6; the maximum value is 32766.


Polyface Mesh

Create an edge-defined Coons surface patch mesh

CADDIT® is a registered trademark in Australia. All Rights Reserved. Comments concerning the content of this site should be addressed to our webmaster. progeCAD is a trademark of ProgeCAD srl. Autodesk® and AutoCAD® are both registered trademarks or trademarks of a third party, and used only for comparison purposes. All other trademarks, trade names or company names referenced herein are used for identification only and are the property of their respective owners. Legal and Terms of Use. Google. Find us on Google+.