Altium Designer Documentation


Created: December 5, 2018 | Updated: January 18, 2019
Now reading version 20.1. For the latest, read: StartMating for version 21
Applies to Altium Designer versions: 19.0, 19.1, 20.0, 20.1 and 20.2

Parent page: MultiBoardAssembly Commands

The following pre-packaged resource, derived from this base command, is available:

Applied Parameters: None


This feature is used to start the mating mode on a multi-board assembly (*.MbaDoc). A mate is a connection formed between two separate objects. The connection is at a user-selected point on a surface on each object. Once mated, the objects will re-orient so their surface planes and their perpendicular axes are aligned.

For a high-level look at multi-board design within Altium Designer, see Designing Systems with Multiple Boards.


This command can be accessed from the Multi-board Assembly Editor in the following ways:

  • Choose Tools » Mating from the main menus.
  • Choose  from the Active Bar.
  • Use the Shift+Ctrl+A shortcut.


After launching the command, Mating mode is activated. Hover the cursor over an object to be mated. As the cursor is positioned over a surface on the object, that surface will change color (to gray), and display potential mate sites (glyphs).

On a planar surface, select from nine glyphs, located at the center, corners and mid points of the bounding rectangle. On a cylindrical surface, select from two glyphs, located along the axis at each end of the cylinder.

Each glyph is a potential mate site. The glyph that is currently closest to the cursor is highlighted by a larger green dot. Click the cursor anywhere over the surface to accept the highlighted glyph as the first mate site (the Target). Once selected, the Target is marked by a purple dot. As the cursor is moved off the surface it will turn green, indicating that the Target lies on that surface.

Repeat this process on the second object to define the second mate site (the Source), which will be highlighted using a brown dot.

As soon as the Source is defined, the Source object will move so that the Source site and the Target site are mated (located together), with their perpendicular axes and their surface planes aligned. The Mate location is indicated by a circular arc, which remains visible through other objects (when the Mate is selected), and the perpendicular axis of the mate location is displayed using a dashed purple line.


  1. When objects are mated, they are locked together and move as a single object.
  2. If it is difficult to select a glyph, for example, selecting the center of a hole in an object, or the wrong glyph was selected, you can change the Target glyph before moving on to define the Source glyph.
  3. As the cursor continues to be moved over the plane containing the Target, each glyph highlights in green when it becomes closest to the cursor. The current Target remains highlighted in purple. If a different glyph is required, position the cursor to highlight it in green, then left-mouse click to nominate it. 
  4. If it is not possible to define a Mate on a mounting screw, hide the screw (right-click on the object in the Multi-board Assembly panel) and use the screw hole instead.
  5. The second mate site must be located on a different object from the first mate site. If a second surface is selected on the same object as the first mate site, the action is interpreted as choosing a new first mate site.
  6. Mated objects can be mated to a third object.
  7. The workspace view can be changed while you are defining a Mate:

    • Ctrl+Right-click and drag to zoom in/out.
    • Shift+Right-click and drag to pivot the workspace view around the click location.
  8. Press Esc to abort the mating process and drop out of Mating mode.
The Status bar at the bottom left of the editor lets you know you are in Mating mode.


Found an issue with this document? Highlight the area, then use Ctrl+Enter to report it.

Contact Us

Contact our corporate or local offices directly.

We're sorry to hear the article wasn't helpful to you.
Could you take a moment to tell us why?
200 characters remaining
You are reporting an issue with the following selected text
and/or image within the active document: