Linking GD&T Symbols to Dimensions

You can snap an arrow of GD&T symbol to a dimension line or link feature control frame parameters with a dimension.

Snapping arrow of GD&T symbol to dimension line

In order to snap an arrow of a feature control frame or datum feature symbol to a dimension line, you should select the desired dimension using object snapping during positioning of arrow's starting node.

Alternatively, a dimension can be selected using the following automenu option:

Upon activating this option, a click anywhere in the drawing window snaps the GD&T symbol to a linear or radial dimension nearest to the point of clicking.

For linear dimension, the arrow of the GD&T symbol will become an extension of the dimension line, i.e. the starting point of the arrow will coincide with one of the ends of the line, and the angle of the arrow will be the same as the angle of the line. For radial dimension, the witness line of the arrow will become an extension of the dimension line, while the arrow itself will be normal to the witness line. In both cases, you should then specify an ending node of the arrow

For datum feature symbols snapping an arrow to a dimension only affects the arrow. For feature control frames it also affects tolerance parameters. Upon snapping an arrow to a dimension, the tolerance value in the feature control frame is calculated automatically considering the value of the selected dimension and the specified precision. In the meantime the Dimension box in frame's parameters is non-editable and is received from the linked dimension. So, the frame parameters change automatically upon changes in value of the linked dimension.

To break connection between tolerance parameters and the dimension value, use the following automenu option:

This option only breaks the link with dimension value, and doesn't affect the arrow snapping.

To cancel the arrow snapping, you should enter the mode of arrow's starting node positioning by clicking the node's manipulator with, and then use the following automenu option:

This option only cancels the arrow snapping, and doesn't affect the link with the dimension value.

Linking feature control frame parameters with a dimension

A link between tolerance parameters and dimension value may also be established without snapping the arrow. To do so, use the following automenu option:

Upon activating this option, you should select a desired dimension by clicking it with . In result, the tolerance parameters will be linked as described above. Unlike arrow snapping, this option allows to select not only linear and radial dimensions, but also angular and arc dimensions.

The Show Dimension Value option is additionally enabled for demonstration.

Despite the lack of visual connection between the feature control frame and its linked dimension, the positions depend on each other. Dragging the frame with mouse results in dragging also the dimension and its parent lines, regardless of whether the lines are fixed or not. In order to move the frame without moving linked elements, use the manipulator of frame's anchor point.

To break connection between tolerance parameters and the dimension value, use the following automenu option:

See Also:

•GD&T Feature Control Frame

•GD&T Datum