enter image description here

enter image description here

I’m in the process of adding an ik-control to my thigh that counters the extreme twisting on bones “DEF_thigh.L.001” and “DEF_thigh.L.002”.

The “copy rotation” bone constraint on “DEF_thigh.L.002” is meant to counter the extreme twist of “DEF_thigh.L.001” when using the “CTRL_ThighCounterTwist.L.001” control. When built properly, everything below bone “DEF_thigh.L.001” does not crush when rotated to its extreme axis.

Problem is, despite implementing Dikko’s controls, “DEF_calf.L.001” is rotating and crushing when pushed to its extreme, even if the axis of “DEF_thigh.L.002” isn’t moving as intended ( as seen in Dikko’s video ).

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Below are things I’ve checked.

I checked to ensure my "CTRL_ThighCounterTwist" for both sides was the correct orientation in relation to the "DEF_thigh" bones.

When I applied "copy rotation" I ensured the constraints are "local space” and that the mixing came "after the original". For "DEF_thigh.L.002".

I then checked the targeted bone within the "copy rotation" attribute to ensure it was targeting the respective "CTRL_ThighCounterTwist".

I also checked to ensure "deform" was enabled under "bone properties" for my deform bones only.

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The only other things I think would cause my issues are my FK and IK bone properties and their drives. But they seem to be fine in terms of what's enabled for my FK and IK controls.

The only other thing I can think could be an issue is a potential parent-to-child relation somewhere or maybe a misapplied driver data path?

I've provided visuals of both my thigh and arm bones. The arm bone constraints work great and the thighs' constraints are an exact copy of the arms'.

I'm at a complete loss as to what I am doing wrong in my file so any help is appreciated!

PS: Nathan provided me with an awesome way to work around this using weight paint. But Dikko's tutorial has no weight paints yet and I'm trying to match what he did exactly. But if I have to fix it that way, I'll give it a shot.

Blender File: https://bit.ly/3LE1MTJ

Video ( 46 minute mark ): https://bit.ly/3GolbUI

  • 1
    $\begingroup$ About your PS, do you mean something like screentogif.com ? (With ffmpeg.org you even can create a video file. But this site here only accepts animated gif images, max 2 MB) $\endgroup$
    – Blunder
    Feb 11, 2022 at 16:26
  • 1
    $\begingroup$ Please read here for how to include gifs in your questions and answers. You may also see any of the questions on our meta that are tagged faq for helpful information about the site. $\endgroup$
    – Timaroberts
    Feb 11, 2022 at 16:28
  • $\begingroup$ @Blunder Thanks so much! I'll be sure to check it out and educate myself on the methods you've suggested. 😊 $\endgroup$
    – Mulder
    Feb 11, 2022 at 16:31
  • $\begingroup$ @Timaroberts Thank you! I'll be sure to check out both of those sections. 👍 I just know gifs and videos can help provide far more information than static images can. I want to make the process easier for all involved haha. $\endgroup$
    – Mulder
    Feb 11, 2022 at 16:32

2 Answers 2


Your file's armature isn't colored for me. It looks like "purple bone" here is DEF_thigh.L.001 and "yellow bone" is CTRL_ThighCounterTwist.L.001. In the future, referring to bones by their names is a better idea than by colors, because names are unique and colors aren't.

The rig appears designed such that rotating CTRL_ThighCounterTwist.etc rotates DEF_Thigh.etc but not its children, and it does that.

However, your mesh is still deforming all the way to the knee because your mesh is weighted to DEF_thigh.L.001 all the way to the knee:

enter image description here

The thigh twist bone is not being affected by the rotation of the upper thigh bone, but that doesn't matter, because the mesh that should be weighted to the thigh twist bone is weighted to the upper thigh bone.

  • $\begingroup$ Hey, @Nathan; thanks so much for the visual! It’s very clear and informative. I sincerely thank you for providing it. : D However, I'm trying to match Dikko's method exactly and he’s not applied weight paints on his model yet ( that I can tell ). I know for sure there's something I'm doing wrong because the IK constraints in my arms work fine, and they don't have weight paints either. I’ve updated my source file to fix some naming conventions and plan on updating this post with clearer visuals and what I’ve tried since my original question based on your feedback! 👍 $\endgroup$
    – Mulder
    Feb 28, 2022 at 5:54
  • $\begingroup$ I've updated my question’s terminology and visuals to hopefully make it clearer based on your feedback! Also gave you credit for helping me to improve my question because I did not realize how vague spots of it were until you pointed those areas out. So seriously; thank you for that! Until then, I’ll mess around with your weight paint suggestion once I’m done with Dikko’s other rig setups because I’m at a loss of what else to do to fix my thigh problem haha. Unless that’s something I should do now instead of later? $\endgroup$
    – Mulder
    Feb 28, 2022 at 6:19

Guess who solved their own question - me!

After recreating the leg’s child-to-parent relations, drives, controls, and running into the same issues, I deduced the problem was a relation of the bones to the mesh. Nathan’s response about weight paints sparked this thought into my head.

I then recalled a similar issue I had fixed with an area of the spine.

Below’s my solution:

[A] Select your mesh in “obj mode”.

[B] Go to “obj properties” and to “relations”. enter image description here

[C] Remove ( click x ) the parent ( in my case it was legature ).

[D] Go to modifier properties and select “armature”. Remove that. enter image description here

[E] With the mesh selected, then shift-select the armature.

[F] Press [CTRL]+[P] and assign “automatic weights”.

This resolved the crunching I had seen around the knee and now my mesh works like Dikko’s!

I’m presuming my original issue was because I did not update the mesh to bone relations when adding these constraints? I will keep in mind moving forward.


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