About the Thicken Sketch Command
Use the Thicken Sketch command to create a thickened solid by applying a specified thickness to the section outline. Thicken Sketch is useful when you create simple features with a uniform thickness.
Consider these rules for adding a thickness:
You can apply the thickness value to either side of the sketch or to both sides.
For the thickness dimension, you can specify only a positive value.
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You cannot include text in a section sketch.
For some types of thickened features, the Cap with model geometry option can be used to specify how to cap and attach a thickened feature to the model. It is available under the following conditions:
Extrude or Revolve feature
Thicken Sketch is selected.
The sketch is an open sketch.
One or both sketch end points intersect the model solid geometry.
The system detects at least one surface that can be used to cap and attach the Extrude or Revolve feature to the model.