The Cheat Sheet

This section is meant as a quick summary to introduce users to some important rigging concepts at a glance. These tips are categorized by skill level, because many if not all of the expert tips are unnecessary to understand at first, and are more likely to confuse beginners. If you have a tip that you feel should be here, please send me a private message or post it in the rigging thread and I will add it.

WHAT EVERY BEGINNER SHOULD KNOW:

Always clear your transforms before beginning.
Always either clear the scale and rotations (alt+r/s) or apply the scale and rotations (ctrl+a) to your mesh, and clear the transformations of the armature object completely (alt+g/s/r) before beginning a rig. The mesh should also be centered so the feet are on the ground plane (grid), the Z axis (blue) runs through the exact middle of the character (bellybutton), and the X axis (red) runs in the same direction as the arms. In front view (numpad 1) you should be looking at the front of your character, with the Z axis through his center, and the X axis under his feet. It can also be useful to move the object center for each of your characters' meshes to the grid center by putting the cursor to 0,0,0 in the 'view->view properties' window, selecting the mesh and choosing 'center cursor' in the edit panel. These steps will help ensure you do not run into problems from adding initial transformations when using constraints or modifiers, which can produce difficult to understand problems which are hard to fix later on. Remember you can always reposition your mesh in edit mode to move it without changing the object center.

Always refer to the terminal while rigging to check for 'dependency cycles'.
A dependency cycle is a loop where component A depends on component B and B in turn depends on A. It may have worked for Escher, but it won't work here because it is a logic problem and will produce unpredictable behaviour (even if sometimes it seems like it might be okay - it's a problem waiting to happen). No matter what, always fix your dependency cycles! A clean (and sturdy) rig should have none.

Create only one armature object per one character.
This rule can be broken later on, when you understand why you are wanting to break it, but until you do - stick to one!

Arms, legs, and other symmetrical meshes are best created using the mirror modifier.
In order for the mirror function of the weight paint tool to work, symmetrical components need to be contained in the same mesh. A good rule to follow is separate meshes up and down, same meshes left to right. Arms can be separate from the body, but the left arm should be part of the same mesh as the right arm. An easy way to do this is to use the mirror modifier on the component you wish to mirror, and have the object center at the center of the character (or at 0,0,0). This also ensures perfect symmetry, which is often needed for some rigging tools to work properly.



WHAT EVERY NOVICE SHOULD KNOW:

Bone roll should always be inverse from one side to the other.
A negative roll value on one side means the other side should have the same but positive value, and vice versa. This ensures the behaviour of the bones is properly symmetrical and is important for functions like 'mirror pose'. When scaling negatively to copy bones from one side to the other, the values will rarely ever be correct. You can either enter the values manually, or a neat trick is to enable X-axis mirroring in the armature options and select all the bones with the proper rotations and press "ctrl+r" and the other side should snap into the appropriate position. The bones must be named properly (L and R) for this to work.

Separate the bone types using bone groups/layers to keep the rig organized.
While working on a rig it is useful to have your bones organized into 3 main types: deformers, mechanisms, and controls. Deformers are responsible for influencing the mesh, mechanisms are required to make components work, and controls are to be used by the animator. Keeping it clean helps prevent problems, helps in fixing problems, and makes it less overwhelming.

Bones can be hidden (h) to clear a working space if you don't want to move any to another layer. (Unhide with alt+h)

Shift+w in pose mode will allow you to quickly toggle settings for a selection of multiple bones at once.



WHAT EVERY EXPERT SHOULD KNOW:

You can move bone chains into position for awkward angles in pose mode then apply to edit mode with "ctrl+a".
This little trick is for the early stage when only deform bones are being laid out so there is nothing to break by applying. Instead of tweaking each joint individually, or moving a chain by pivoting around the cursor again and again, sometimes it is just quicker and easier to rotate and scale the bones into position in pose mode to keep them aligned. Then apply he new position to edit mode.

The little "s" in the bone options will prevent a bone from inheriting scale from its parent.

Pressing "shift+G" with a bone selected will allow you to easily select all bones in the same bone group.

Use the mirror modifier without applying it.
**Warning: It has since come to my attention that asymmetrical shapekeys are not possible with the mirror modifier**
Using the mirror modifier above the armature modifier with 'vertex groups' enabled will allow a rig to be posed asymmetrically without needing to apply the mirror modifier. This can keep your file sizes down, since only half the mesh data is needed. 'Mirror Weights' must be enabled in the weight paint tool for it to work properly, and the bones must be named properly (L or R) as well.

Use multiple armatures to sidestep dependencies.
Bones in one armature can directly drive the IPO of bones in another armature. Bones can be constrained to a mesh deformed by bones in a separate armature. There are times where dependencies need to be sidestepped this way. A second armature can help you out of a tight spot, but try to keep all of your control bones in the same armature if you can. Separate controls can lead to frustrations when animating...

You can "ctrl+left click" on a bone layer to highlight it.
This is useful for showing other users what layers are for animation, and can be used when linking your rig into a new file.

Control which bones are auto-weighted to each mesh.
When using bone heat weighting to auto-weight bones from a single armature onto multiple mesh objects, it is very likely that you do not want all of the bones to effect every mesh. For example if your legs were separate from the torso, the bones in the torso do not need to be included on the leg mesh and vice versa. You can exclude a selection of bones from the auto-weighting process by disabling the 'deform' option. Select them all, press "shift+w" to toggle 'deform' off, create your bone heat weighting, and then re-enable the 'deform' option on the temporarily disabled bones. The mesh will have been weighted, excluding the bone groups that were disabled.