Dimension Tangent to an Arc or Circle
When adding sketch dimensions from one circle or arc to another, a dimension will be added between the center points by default. However, by selecting the circle and/or arc when adding the dimension, the properties for that dimension now have options to change where the extension lines display.
These options can be changed at any time for dimensions that fit this criteria by editing the Dimension Properties in the Property Manager.
In addition, if you know the desired orientation of the dimension prior to adding it, you can ‘set’ the Arc Condition properties simply by the way you add the dimension to the sketch.
Below is a dimension added by selecting the two circles and placing the text. Switching to the LEADERS Tab in the Property Manager shows how the Extension Lines can be changed.
Setting the Arc Condition on Insert
WHILE adding the dimension, if you hold SHIFT, you can Snap to the Minimum, Center or Maximum Arc Condition depending on what part of the circle/arc you select.
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** These images have centerlines drawn at 45 degrees off of the center to center position of the two circles for illustration purposes only.
– When the user holds SHIFT while adding the dimension between the two circles, if the cursor is between the ’90 degree window’, the ARC CONDITION gets set to minimum. Click to capture Arc Condition. |
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– While still holding SHIFT, if the cursor position moves outside the ’90 degree window’, the ARC CONDITION changes to CENTER.
Click to capture Arc Condition. |
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– While still holding SHIFT, if the cursor is moved to the imaginary ’90 degree window’ on the far side of the circle, the ARC CONDITION changes to MAXIMUM.
Click to capture Arc Condition. |
Both methods yield the same end result. By using the ‘SHIFT’ method, the user can save a couple steps with each dimension.
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Darin Grosser is a SolidWorks Elite Application Engineer, Certified SolidWorks Expert and a senior member of the technical staff at DASI Solutions, a SolidWorks Value Added Reseller with locations throughout Michigan and Indiana. He is a regular contributor to the DASI Solutions Blog.