Working with a Standard Dimension Object on a PCB in Altium Designer

Parent page: PCB Objects

A placed Original Dimension.

Summary

An original dimension is a group design object. It places dimensioning information on the current PCB layer. The dimension value is the distance between the start and end markers, measured in the default units.

Availability

Original 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 » Dimension from the main menus.
• Click the  button on the Place Dimension drop-down () of the Utilities toolbar.
• Click the  button on the Utility Tools 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 and click or press Enter to anchor the dimension start point.
2. Move the cursor to the required end point, then click or press Enter to anchor this point and complete placement.
3. Continue placing further standard dimensions, or right-click or press Esc to exit placement mode.

Additional actions that can be performed during placement are:

• Press the L key to flip the dimension to the other side of the board – note that this is only possible prior to anchoring the dimension's start point.
• 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 original dimension object directly in the workspace and change its location, orientation and position of its start and end points, graphically.

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

A selected Original Dimension.

• Click & drag A to move the start point of the dimension.
• Click & drag B to move the end point of the dimension.

• Click anywhere on the dimension – away from editing handles – and drag to reposition it. While dragging, the original dimension can be rotated or mirrored:
  • Press the Spacebar to rotate the original 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 original 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: Dimension

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

The Dimension dialog.

The 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 original dimension object to be changed, which will be applied when placing subsequent original 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 original dimension object.
• Placing the cursor over an original dimension object, right-clicking and choosing Properties from the context menu.
• Using the Edit » Change command and clicking once over a placed original 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. Original 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.