Need help with Captain Blender :)

Hi all,

Can somebody please help me with this rig, it’s my third attempt to rig “Captain Blender” from the book “Introducing Character Animation in Blender”, and every time I try to move it, it kind of explodes!

I am on page 158, here is a link to my rig:

There are some typos in the rigging section. Check out the errata pagewhich has corrections.

Thanks Orinoco, but even after I change those points mentioned in the errata, it’s the same… bones flying all over the place when I try and move something:no:

Ok, there’s more going on than just a few misplaced bones.

If you move the Root bone a bit in pose mode, after the rig goes whack, take a look at the Blender terminal window - that small window that says “found python” when you open Blender. Don’t do this standing up. :evilgrin: It’s full of Cyclic Dependancies. Which cause your rig to do those odd dances when you try to pose it.

Most of them are probably due to some Constraint that was misapplied. Common mistakes are incorrect chain length; misspellings of target objects or bones, which makes the Constraint name field red (the first in the panel, usually ‘Const’ unless you change it).

Anyway, your Neck IK constraint has a chain length of zero, should be one, and the two IK_Arm Copy Rotation constraint were targetted to Hand, instead of Hand.L and Hand.R, so the constraint wasn’t doing anything.

Fixing those doesn’t get rid of all the dependancies. You’ll have to go back through the rig and check each one that shows up.

some errata I’ve noted: (Table 4.1 page 178/179)

Bicep.L parent Torso, not UpperBody
Rib3.L parent SpineStretch.004 not 002
Rib1.L parent SpineStretch.002 not 004
SpineStretch.002 copy loc and copy rot Spine.2 not 4 stretch to Spine.3
SpineStretch.003 stretch to Spine.4
SpineStretch.004 copy loc and copy rot Spine.4 not 2 stretch to IK_Spine
HeelDeform.L parent Foot.Mech.L not Foot.L
Ball.L parent Heel.L not FootRoot.L
Toes.L does not copy loc Ball.L
Torso parent Root

Shoulder.L, Spine.1 ARE deform bones
neckloc, SpineStretch.002, SpineStretch.003, SpineStretch.004 are NOT deform bones

btw, that’s a fairly odd shaped mesh for the rig you’re building. Good luck.

You may want to check your weight paints and envelopes-If all else fails just look at the .blends that came with the disc. I am using the book as a guide, not as a tutorial, so I will be creating my own character with its differences from Cap’n Blender. I usually never follow books exactly, because when yours isn’t exact, you usually get frustrated. That’s why you should use it as guidelines, not an exact tutorial. Believe me, it will ease some stress. You could probably make a simpler character and follow the book, because rigging can go haywire with CB’s muscular body. Or just use his .blends, because those are setup exact to the book.

If anything though, don’t give up!

Thanks so much Orinoco! I haven’t tried the changes yet, only just read the message, but it is great of you to give me such a detailed response. I’ll check all that and let you know how it goes :slight_smile:

Noobhaxor: Thanks for the advice also. I have temporarily lost the disc for the book, so don’t have the finished product to look at, if someone could upload it, that would be good too. :o


Here are the complete tutorial files for the book. Hope this is helpful!


Thanks Bugman, that will help a lot to see how it should be done :slight_smile:

Great book by the way :wink:

That’s funny, that I find this thread today, I was just about to open it myself.

I have the same problem, I’m also stuck on page 158. When I add the IK for the arms the arms go funky, as soon as I move IK_Arm.L or .R. In my case it is only the arms, so I just have a few bones to look for the problem, but I don’t find it. I also followed the instructions really closely, so I don’t know what is wrong.

Could someone be so nice and have a look at the file? Would be great, thank you!

Also when I compare it to the figure 4.45 (the lower one) on the picture you can see a parenting line going from the root of IK_Arm.L to somewhere. In my rig this line is missing at that point. Might this be the problem?

Thank you for your help!


Could someone be so nice and have a look at the file? Would be great, thank you!

The bone IK_Arm.L is parented to Forearm.L in the blend you uploaded. You must not have an IK target being parented by the bone it’s supposed to control. I’d have to check, but I believe in the original file IK_Arm.L is parented to Torso. At least for this problem, it doesn’t really matter. Go into Edit Mode, and unparent it from Forearm.L and the crazy IK problem will go away.

Hi bugman_2000!

Thank you so much for looking into this, it solved my problem! :yes: Now I can happily continue blendering on the beloved Captain Blender.

I guess it was parented, because when you Shift+D the hand bone also the parenting will be duplicated…? Not sure if it mentioned somewhere to unparent it.

I also must say it’s a great book, so thank you again! :cool: