What it does
Auto Mate finds where parts touch (face to face, hole to shaft) and creates all the mates for you. It suits assemblies imported from STEP, where the parts are already in the right positions but have no mates.
Where to find it
Assembly › Mates › Auto Mate

Steps
- Select the parts you want. If you select none, all visible parts are used.
- Click Auto Mate.
- Check the list shown, then confirm. Click Cancel to undo everything.
Note: A sub-assembly inserted as a rigid body must first be released with Rigid Body › Ungroup Rigid Body. Only then can Auto Mate create the joints inside it.
