Leader Dimension

Parent page: Dimension

Placed Leader Dimensions

Summary

A leader dimension is a group design object. It allows for the labeling of an object, point or area. The label text can be encapsulated in a circle, a square, or not at all, while the pointer can be an arrow or a dot.

Availability

Leader dimension objects are available for placement in the PCB Editor only by clicking Home | Dimension | 

then selecting Leader from the drop-down list.

Placement

After launching the command, the cursor will change to a cross-hair and you will enter dimension placement mode. Placement is made by performing the following sequence of actions:

1. Position the cursor then click or press Enter to anchor the dimension start point (this is the location of the arrowhead or dot).
2. Move the cursor then click or press Enter to anchor a series of vertex points that define the shape of the leader.
3. After placing the final required vertex point, right-click or press Esc to effect placement of the text label and exit placement mode.

Additional actions that can be performed during placement are:

• Press the + and - keys (on the numeric keypad) to cycle forward and backward through all visible layers in the design, respectively, to change placement layer quickly.
• Press the Tab key to access an associated properties dialog, from where properties for the dimension can be changed on-the-fly.

Graphical Editing

This method of editing allows you to select a placed leader dimension object directly in the workspace and change properties such as the position of its text, its shape and its reference point graphically.

When a leader dimension object is selected, the following editing handles are available:

A placed Leader Dimension

• Click & drag A to move the start point of the dimension (i.e. the position of the arrowhead).
• Click & drag B to move the end point of the dimension (i.e. the position of the text label).
• Click & drag intermediate handles to change the shape of the leader.

If the leader dimension object is totally non-referenced (i.e. it is not attached to a reference design object) click anywhere on it – away from editing handles – and drag to reposition it. While dragging, the leader dimension can be rotated or mirrored:

• Press the Spacebar to rotate the leader dimension counterclockwise or Shift+Spacebar for clockwise rotation. Rotation is in accordance with the value for the Rotation Step defined on the PCB Editor – General page of the Preferences dialog.
• Press the X or Y keys to mirror the leader dimension along the X-axis or Y-axis respectively.

Non-Graphical Editing

The following methods of non-graphical editing are available:

Via an Associated Properties Dialog

Dialog page: Leader Dimension

This method of editing uses the following dialog to modify the properties of a leader dimension object.

The Leader Dimension dialog

The Leader Dimension dialog can be accessed during placement by pressing the Tab key.

After placement, the dialog can be accessed in one of the following ways:

• Double-click on the placed leader dimension object.
• Place the cursor over the leader dimension object, right-click then choose Properties from the context menu.

Quickly change the units of measurement currently used in the dialog between metric (mm) and imperial (mil) using the Ctrl+Q shortcut. This affects the dialog only and does not change the actual measurement unit employed for the board as determined by the 

and  buttons in the Home | Grids and Units area of the main menus.

Via the PCB Inspector Panel

Panel page: PCB Inspector

The PCB Inspector panel enables you to interrogate and edit the properties of one or more design objects in the active document. Used in conjunction with appropriate filtering, the panel can be used to make changes to multiple objects of the same kind, from one convenient location.

Notes

1. A leader dimension object can be moved in the following ways:
   1. Selecting both the dimension object and the object that is being dimensioned. The whole can be dragged to a new location as required.
   2. Selecting the object that is being dimensioned only. The dimension will follow the object. The segment of the leader dimension – between the arrow/dot and the first defined elbow – will expand/contract to keep the relationship between dimension and object dimensioned.
   3. Selecting the dimension object only. It is important to note that the dimension cannot be moved on its own if it is referenced by a design object. To move the dimension only, it must first be detached from the object it is dimensioning.
2. When the reference to which a dimension object is attached is deleted, a dialog will open asking whether the dimension should also be deleted. If the dimension is not deleted, it remains in the workspace, but non-referenced.