ISV is used for simulation of cutting tools, but issues are experienced with the quality of CUTTING_SPUN Geometry. There is concern over the accuracy of the 3D model for spinning Geometry. Curves are approximated into straight line segments for standard ball endmills. When the revolve section from the sketch is chosen for "CUTTING", the radius on the end is affected. It is now broken down into linear segments which does not give an accurate representation of the tool. This is a small endmill used for small details on a very expensive part; accuracy is required. What approach would give better results? What control is there of the tolerances for Cutting_Spun/Non_Cutting_Spun tool geometry?
Solution
There is some control over this behavior in the NX Customer Defaults. The tolerance that creates the facets for the tool which result in the spinning geometry can be changed here:
1. Select 'File-->Utilities-->Customer Defaults'.
2. Expand 'Manufacturing' and highlight 'Simulation & Visualization'.
3. Select the 'ISV' tab.
4. Set the 'Faceting Tolerance for Collision Detection'.
The default is 0.5 mm (or .0197"), which is fairly large for a 1/32" ball mill. Consider a much smaller value here to better support small tools.
It is important to note that the gouge checker and the material removal IPW do NOT use this relatively rough tolerance. For these calculations, the chordal tolerance is used so the accuracy is much higher than what is seen in the graphics.
For the IPW:
1. Select 'File-->Utilities-->Customer Defaults'.
2. Expand 'Manufacturing' and highlight 'Simulation & Visualization'.
3. Select the 'IPW' tab.
4. Set the 'Chordal Tolerance' field.
For Gouge Check:
1. Select 'File-->Utilities-->Customer Defaults'.
2. Expand 'Manufacturing' and highlight 'Simulation & Visualization'.
3. Select the 'Gouge' tab.
4. In the Tolerance group, set the 'Chordal' field.
Notes and References
Hardware/Software Configuration
Platform: all
OS: n/a
OS Version: n/a
Product: NX
Application: CAM
Version: V10.0.3
Function: ISV
Ref: 001-8002593