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Copying and arranging in a circle

8/8/2013
Version 0.13
This article explains how to copy a solid and arrange in acircle. It is possible to create shapes as shown in the following figures.
Polar pattern 1
Polar pattern 2
  1. Click [File]-[New] in menu bar and create new document.
  2. Move to Part Design workbenchPartDesign workbench.
  3. At first, create a solid to be copied.
    1. Create new sketch planeSketcher_NewSketch on the XY plane.
      Create Sketch
    2. Create two straight linesSketcher_Line, one polylineSketcher_CreatePolyline and two arcsSketcher_Arc. You can set these positions in rough because these will be adjusts in the restraint operation.
      Sketch
    3. Cnnect wires with Coincident constraintConstraint_PointOnPoint as shown in a following figure. At the same time, set the start point of two lines forming an arc to the origin.
      Connect Sketches
    4. Apply Parallel constraintConstraint_Parallel to the right side two straight lines. Then apply same constraint to the left side two straight lines in the same way.
      Parallel Sketches
    5. Select two lines forming a arc and apply Internal Angle constraintConstraint_InternalAngle. In this example, we set the angle to 15 degrees.
      Angle constraint
    6. Select two lines forming a arc and switch them to auxiliary linesSketcher_AlterConstruction. Auxiliary lines are displayed in blue color.
      Auxiliary lines
    7. Click Close on Task tab in Combo View to exit sketch editing mode and PadPartDesign_Pad the sketch. Now we get a solid to be copied.
      Pad sketch
  4. Next we copy the solid and arrange the copies in a circle. Move to Part Design workbenchDraft workbench.
  5. Select "Pad" in parts tree and execute Array toolDraft_Array.
  6. Select "Array" newly created in the parts tree to set array type, axis for a circle arrangement, number of copies and so on.
    ComboView Array Combo View for Array
  7. In this example, we set only following parameters and create 12 copies of the solid and arrange them in a circle.
    • Array Type : Polar
    • Number Polar : 12
  8. Shapes become as shown in the following figure after copy operation is finished.
    Arrayed solids
    If you substract these solids from a cylindrical solid with boolean operation, you can get a solid like a gear shape.
    Arrayed solids
References:
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