Construction Aid Circle > Tangential (Construct Menu)

This command draws a Construction Aid circle which has a given center point and is tangent to another line (or Construction Aid line), circle (or Construction Aid circle) or ellipse.

If a Construction Aid circle is to be drawn while working in isometric or dimetric views, this must be done with the command Construction Aid Ellipse > Vector - Vector because the result on the page is not circular but elliptical.

Any part object in an existing object can be identified as the reference object. This can be a side of a rectangle, the arc of an ellipse segment or a circle segment within a surface.

The identified (part) object is referred to as the "Reference Object". After identification, a straight line appears on which the circle's center point will lie. This is known as the "Reference Straight Line".

The position of the circle and therefore the tangent point of the objects can be entered using the mouse, by clicking anywhere in the drawing. A perpendicular is dropped from this position to the reference object in order to work out the tangent point.

If a circle is identified as the reference object, the position of the reference point determines which side of the reference circle the tangent point should lie. The intersection of the reference straight line with the reference circle nearer to the reference point is used as the tangent point.

The center point of the circle can be entered using the mouse, by clicking anywhere in the drawing. A perpendicular is dropped from this point to the reference straight line to work out the center of the circle.