Working with an Angular Dimension Object on a PCB in Altium Designer

Parent page: PCB Objects

A placed Angular Dimension.

Summary

An angular dimension is a group design object. It allows for the dimensioning of angular distances.

Availability

Angular dimension objects are available for placement in the PCB Editor only. Use one of the following methods to access a placement command:

• Choose Place » Dimension » Angular from the main menus.
• Click the  button on the Place Dimension drop-down () of the Utilities toolbar.

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 over the first reference object and click or press Enter to anchor the first dimension reference (the inside reference).
2. Move the cursor to the next required position associated with the first object being dimensioned and click or press Enter to anchor the second dimension reference (the outside reference).
3. Position the cursor over the second reference object and click or press Enter to anchor the third dimension reference (the inside reference).
4. Move the cursor to the next required position associated with the second object being dimensioned and click or press Enter to anchor the fourth dimension reference (the outside reference).
5. Place the dimension text for the angle as desired and then click or press Enter to complete placement.
6. Continue placing further angular dimensions, or right-click or press Esc to 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 angular dimension object directly in the workspace and change properties such as the position of its text and its reference points, graphically.

When an angular dimension object is selected, the following editing handles are available:

A selected Angular Dimension.

• Click & drag A or B to change the position of the dimension text and extension line length.
• Click & drag C and E to detach the dimension from the first reference object.
• Click & drag D and F to detach the dimension from the second reference object.

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

• Press the Spacebar to rotate the angular dimension anti-clockwise 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 angular 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: Angular Dimension

This method of editing uses the following dialog to modify the properties of an angular dimension object.

The Angular Dimension dialog.

The Angular Dimension dialog can be accessed prior to entering placement mode, from the PCB Editor – Defaults page of the Preferences dialog. This allows the default properties for the angular dimension object to be changed, which will be applied when placing subsequent angular dimensions.

During placement, the dialog can be accessed by pressing the Tab key.

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

• Double-clicking on a placed angular dimension object.
• Placing the cursor over an angular dimension object, right-clicking and choosing Properties from the context menu.
• Using the Edit » Change command and clicking once over a placed angular dimension object.

Via the PCB Inspector Panel

Panel page: PCB Inspector, PCB Filter

The PCB Inspector panel enables the designer to interrogate and edit the properties of one or more design objects in the active document. Used in conjunction with appropriate filtering - by using the PCB Filter panel, or the Find Similar Objects dialog - the panel can be used to make changes to multiple objects of the same kind, from one convenient location.

Via the PCB List Panel

Panel page: PCB List, PCB Filter

The PCB List panel allows the designer to display design objects from one or more documents in tabular format, enabling quick inspection and modification of object attributes. Used in conjunction with appropriate filtering - by using the PCB Filter panel, or the Find Similar Objects dialog - it enables the display of just those objects falling under the scope of the active filter – allowing the designer to target and edit multiple design objects with greater accuracy and efficiency.

Tips

1. An angular dimension object can be moved in the following ways:
   1. Selecting both the dimension object and the objects that are being dimensioned. The whole can be dragged to a new location as required.
   2. Selecting an object that is being dimensioned only. The dimension text will follow the object in its alignment plane only. The dimension extensions will expand/contract to keep the relationship between dimension and object being 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 objects it is dimensioning.
2. The dimension's value automatically updates as its start or end points are moved. Likewise, if the position of an object that a reference point of the dimension is anchored to is changed, the dimension will update and expand/contract to reflect this.
3. When the reference or references to which a dimension object is attached are deleted, a dialog will appear, asking whether the dimension should also be deleted. If the dimension is not deleted, it remains in the workspace, but non-referenced.
4. Angular dimensions are group objects consisting of text and track segments. They can be converted to their set of primitive objects by choosing Tools » Convert » Explode Dimension to Free Primitives from the main menus. Once exploded, a dimension object can no longer be manipulated as a group object.