Working with a Drill Table Object on a PCB in Altium NEXUS
Parent page: PCB Objects
Summary
A drill table, also known as a drill table or a drill drawing legend, is a standard element required for the manufacture of a Printed Circuit Board. The drill table lists the size and number of holes for each drill used on the board. Each drill size can be represented by a symbol, a letter, or the actual hole size. When a drill drawing is generated for the board, each actual drill site is marked by a symbol. The drill table updates in real-time as hole-containing objects, such as pads and vias, are placed or removed from the PCB design.
Availability
A Drill Table can be placed only in the PCB Editor in one of the following ways:
- Click Place » Drill Table command from the main menus.
- Right-click in the design space then choose Place » Drill Table from the context menu.
Placement
After launching the command, a drill table will appear attached to the cursor. Position the table in a suitable location outside the board then click or press Enter to place it.
Additional actions that can be performed during placement while the drill table is still floating on the cursor and before the drill table is anchored are:
- Press the Tab key to pause the placement and access the Drill Table mode of the Properties panel, from where its properties can be changed on the fly. Click the pause button overlay ( ) to resume placement.
- Press the Alt key to constrain the direction of movement to the horizontal or vertical axis depending on the initial direction of movement.
Graphical Editing
Moving a Drill Table
Click and hold anywhere within the drill table then move it to the desired location in the PCB editor design space.
Interactively Resizing a Drill Table
The drill table is automatically sized based on the specified Text Height setting, as well as the number of different hole sizes (rows) and the number of defined columns. To interactively resize the table, click once to select it then click and hold on a corner vertex then move to resize as required. Note that interactively resizing the table will also increase/decrease the font size.
Interactively Switching the Layer Pair to Preview
When the board includes layer-pairs, the displayed layer-pair is controlled by the Layers Pairs option in the Drill Table mode of the Properties panel.
This chosen layer-pair also can be switched using the:
- PCB Editor right-click menu - right-click on the Drill Table then select the required layer-pair in the Drill Table sub-menu as shown in the image below.
- Layer-pair selection menu accessed via the Layer Tab at the bottom of the design space as shown in the image below.
Non-Graphical Editing
The following methods of non-graphical editing are available:
The table size is automatically scaled to fit the included text; reducing the font size (Text Height) will shrink the table to match.
Via the Drill Table Dialog or Properties Panel
Properties page: Drill Table Properties
This method of editing uses the associated Drill Table dialog and Properties panel to modify the properties of a drill table object.
During placement, the Drill Table mode of the Properties panel can be accessed by pressing the Tab key. Once the Drill Table is placed, all options appear.
After placement, the Drill Table dialog can be accessed by:
- Double-clicking on the placed Drill Table object.
- Placing the cursor over the Drill Table object, right-clicking then choosing Properties from the context menu.
After placement, the Drill Table mode of the Properties panel can be accessed in one of the following ways:
- If the Properties panel is already active, by selecting the Drill Table object.
- After selecting the Drill Table object, select the Properties panel from the Panels button in the bottom right section of the design space, or by selecting View » Panels » Properties from the main menu.
Controlling the Assignment of Symbols or Characters
The software automatically assigns a symbol for each hole size. This automatic assignment can be overridden if required in the Drill Symbols dialog. Click the Drill Symbols button in the Properties panel to open the dialog.
Use this dialog to change the style of an assigned Symbol, or choose a Letter (Character) instead.
There are a total of 15 symbols available, as shown below. If there are more than 15 different hole sizes in the PCB, then letters are automatically assigned.
Updating the Drill Table
If there are design changes that introduce changes in the Drill Table, it can be refreshed by selecting it then clicking the button in the Properties panel, as shown below.
The software also can be configured to automatically refresh the Drill Table whenever a design change is made. The option is enabled in the Advanced Settings dialog accessed via the Advanced button in the System - General page of the Preferences dialog.
Editing Multiple Objects
The Properties panel supports editing multiple objects, where the property settings that are identical in all currently selected objects may be modified. When multiples of the same object type are selected manually, via the Find Similar Objects dialog or through a Filter or List panel, a Properties panel field entry that is not shown as an asterisk (*
) may be edited for all selected objects.
Via the PCB List Panel
Panel page: PCB List, PCB Filter
The PCB List panel allows you 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 you to target and edit multiple design objects with greater accuracy and efficiency.
Note
The drill table will appear on all output that includes the Drill Drawing layer. The image below shows an example of drill drawing output, showing each drill site marked by the symbol that has been assigned to that hole size. This example output also includes the Drill Guide layer, which adds a small cross at each hole site.