This dialog allows the designer to specify the properties of an Original Dimension object. 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.
For information on how a placed original dimension object can be modified graphically, directly in the workspace, see Standard Dimension.
The original dimension is considered more of a legacy dimensioning tool, superseded with the enhanced functionality provided by the linear, and other dimension objects.
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.
While attributes can be modified during placement, bear in mind that these will become the default settings for further placement unless the Permanent option on the PCB Editor – Defaults page of the Preferences dialog is enabled. When this option is enabled, changes made will affect only the object being placed and subsequent objects placed during the same placement session.
After placement, the dialog can be accessed in one of the following ways:
Double-clicking on the placed original dimension object.
Placing the cursor over the original dimension object, right-clicking and choosing Properties from the context menu.
Using the Edit»Change command and clicking once over the placed original dimension object.
Start X/Y - defines the location of the center-point of the left-hand extension line.
End X/Y - defines the location of the center-point of the right-hand extension line
Line Width - the current arrow line width (the "thickness" of the lines used to produce the arrows).
Text Height - the current height of the dimension text characters. The character width used to display or print the text is automatically proportioned to this height. A minimum height of 36mil (0.9mm) will allow the string to be legibly photoplotted.
Text Width - the current dimension text stroke width (the "thickness" of the lines used to produce the lettering).
Height - the length of the extension lines.
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 Measurement Unit setting in the Board Options dialog (Design » Board Options).
Layer - the layer the dimension is currently assigned to. Dimensions can be assigned to any available layer, click on the list to view and select a different layer, from all those currently defined for the board.
Unit Style - select how the units should be displayed. Available options include:
None - no units are displayed, only the dimension value (e.g. 846.104).
Normal - units are displayed after the dimension value (e.g. 846.104mil].
Brackets - units are displayed in brackets at the end of the dimension value (e.g. 846.104 (mil)).
Locked - enable this option to protect the dimension from being edited graphically.
If attempting to graphically modify an object that has its Locked property enabled, a dialog will appear asking for confirmation to proceed with the edit. If the Protect Locked Objects option is enabled on the PCB Editor – General page of the Preferences dialog, and the Locked option for that design object is enabled as well, then that object cannot be selected or graphically edited. Double click on the locked object directly and disable the Locked property, or disable the Protect Locked Objects option, to graphically edit the object.
Font - use this field to choose the type of font used for the dimension's text, either Stroke or TrueType. The dialog will present options based on the chosen type.
Select Stroke Font
This area of the dialog and its asscociated option are presented only when the Stroke option is chosen for the dimension text's Font.
Font Name - use this field to choose the required Stroke font. Available options are Default, Serif, and Sans Serif. The Default style is a simple vector font which supports pen plotting and vector photoplotting. The Sans Serif and Serif fonts are more complex and will slow down vector output generation, such as Gerber.
Stroke-based fonts are built into the software and cannot be changed. All three fonts have the full IBM extended ASCII character set that supports English and other European languages.
Select TrueType Font
This area of the dialog and its asscociated options are presented only when the Truetype option is chosen for the dimension text's Font.
Font Name - use this field to choose the required TrueType font. The drop-down list is populated with TrueType and OpenType (a superset of TrueType) fonts found in the \Windows\Fonts folder. Note, the list will only include entries for detected (and uniquely named) root fonts. For example, Arial and Arial Black will be listed but Arial Bold, Arial Bold Italic, etc will not. Use the Bold and Italic options to add emphasis to the text.
Bold - enable this option to make the dimension text bold.
Italic - enable this option to make the dimension text italic.
The use of TrueType fonts in PCB documents will result in more complex Gerber outputs.
To ensure all fonts used in your design are available wherever the design is loaded, enable the Embed TrueType fonts inside PCB documents option, on the PCB Editor - TrueType Fonts page of the Preferences dialog. A substitution TrueType font can also be nominated, for files using TrueType fonts that are not installed locally.