Surface Continuity

1. Surface Continuity

2. Three Types of Continuity Positional Continuity (G0) Tangent Continuity (G1) Curvature Continuity (G2)

3. Aligning Two Curves Object Edit>Align Curve 2 Curve 1 1 Positional (G0) Continuity 1 CV required 1 2 Tangent (G1) Continuity 2 CVs required 1 2 Curvature (G2) Continuity 3 CVs required 3

4. Evaluating Curve Continuity Locators>Curve Curvature Click on a curve or curves to display the curvature plot. Positional Comb plot at different angles Tangent Comb plot aligned but different radius values R1 R2 Curvature Comb plot aligned and radius value matched R1=R2

5. Aligning Two Surfaces Object Edit>Align Surface 2 Surface 1 Positional (G0) Continuity One row of CVs required 1 Tangent (G1) Continuity Two rows of CVs required 1 2 Curvature (G2) Continuity Three rows of CVs required 1 2 3

6. Evaluating Surface Continuity Diagnostic Shading Evaluating Surface Continuity Using ‘Zebra’ Stripes Increase the quality of tessellation to ensure an accurate evaluation. Positional Zebra stripes are disjointed Tangent Zebra stripes are the same width but not smooth Choose horizontal or vertical stripes Curvature Zebra stripes are smooth Increase the number of stripes

7. Blending Between Two Curves Degree 3 Curve Single span 4 CVs Degree 5 Curve Single span 6 CVs Tangency at both ends: 4 CVs Curvature at both ends: 6 CVs Single-span degree 5 curves are recommended for blending curves.

8. Construction Options Preferences>Construction Options Set the construction options before you start to model to define the accuracy of the continuity. Position Tangent Curvature Position........0.1 mm Tangent........0.1 degrees Curvature.....0.1 Position........0.01 mm Tangent........0.1 degrees Curvature.....0.1 Position........0.002 mm Tangent........0.1 degrees Curvature.....0.1

9. When to Use Align Align doesn’t work successfully on adjacent edges: Align works well on one or two (opposite) sides of a surface: Align doesn’t work on periodic surfaces Align doesn’t work well on trimmed edges: Heavy Parameterization (but Align 2008 does)

10. Exercises EX1-Align-curve.wire EX2-Align-surface.wire EX3-Align-two-curves.wire EX4-Align-two-surfaces.wire EX5-Align-eval.wire

11. Other Continuity Tools: Surface Fillet Surfaces>Surface Fillet (Tangent) You will typically use Circular (Tangent) or Curvature. The same value will give different results: In the same space, curvature continuity gives a softer connection but a tighter transition. Constant Radius, Tangent Continuity

12. Surface Fillet Options Fixed Radius, Variable Width Fixed Width, Variable Radius Variable Fillets Click on the blue line to add another radius value. Shift-click to remove. Use the middle mouse button to change the position of the radius locator.

13. Recommended for best-quality layout of surfaces and regular hulls Recommended for quick, tidy modeling Surface Fillet Options

14. Other Continuity Tools: Freeform Blend Workflow: Create a gap between different shaped surfaces Create a Freeform Blend between the two edges Surfaces>Multi-Surface Blend>Freeform Blend Creates a tangent or curvature blend between two edges Chain Select will pick a series of edges.

15. Exercises EX6-Fillet-continuity.wire EX7-Fillet-options.wire EX8-Freeform-hood.wire EX9-Freeform-trunk.wire EX10-Freeform-options.wire

16. Projects P1-Electric-toothbrush.wire P2-Phone-casing.wire P3-Fillet-wheel.wire P4-Electronic-gadget.wire