Teuvo
This page describes how to use circular pattern in sketch mode. This feature is really useful, because drawing twenty different sketches takes a lot of time.
In this example 50 millimeter diameter ball is used as an example. The goal is to end up with a ball which has multiple patterned features on its surface.
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Draw some kind of sketch on a plane which intersects the surface.
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Go to Tools, Sketch Tools and then Circular Pattern....
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First select the Entities to Pattern (the sketch) and then select the revolve parameter, which is in this case the point in the middle of the ball.
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Then go to Instances to Skip and skip instances on to the top and the bottom.
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This will be the result!
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And then just do Revolved Boss/Base and your design should look something like this!
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