Use Point creat Point 1 and Point 2 and Point 3 Use line connect Point 1 and Point 2

Practice 1. Use Shape design

Use Helix

Create Plane > Normal to curve

In xy-plane draw circle 30x50 , Use Pad Go back Part design

Select new Plane as your sketch and draw

Use Rib

Use thickness

Use Split

Use circular pattern

Practice 2. Draw this sketch in zx plane

Create new plane

Draw this sketch in new plane

Use Point creat Point 1 and Point 2

Use "multi-section surface"

Draw this sketch in zx plane Use Extruded

Draw this sketch in zx plane Draw this sketch in xy plane(use spline)

Use sweep Profile->Sketch.5 Guide curve->Sketch.6

Use symmetry and mirror sweep.1

Use Trim select two connect surface And repeat the action in the other connect surfaces

Draw this sketch in xy plane

Use Extruded

Draw this sketch in yz plane Use Extruded

Use Trim cut you dont want

Use Edge Fillet Finish

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