"IK constraint can only be added to Bones"

(Fikcio) #1

Hello, Blenderheads.

This is my problem: Let’s assume a chain of bones; I unparent the last one in order to set a IK constraint; I select the last parented bone and try to add a IK constraint in the Object Constraints tab, but it fails, displaying the message “IK constraint can only be added to Bones”. However, when I set the constraint either by hitting alt+i or shift+ctrl+c, it does work – but the constraint doesn’t show up in the Object Constraints tab.

To add to the confusion, this happens most of the time but not always: sometimes it just works!

This process is new to me, so I might be overlooking something.

I’m using Blender 2.53 beta.

Please help? : (

(ptbbastos) #2

That message you get is because you’re in the Edit Mode of the bones. The solution is to step into Pose Mode of the bones using CTRL+TAB.

Good thing you ran into this issue, this could be a good improvement request for this 2.5x series, because that message should say something like “IK Constraint can only be added in Pose Mode”.

Oh and you don’t need to unparent the last bone in the hierarchy to make the constraint work :slight_smile:

(Fikcio) #3

Thank you. But I still get that message in Pose Mode!

Let me tell you what I’m doing step by step: I create a bone, extrude it twice, unparent the last bone from the chain (even if this is unnecessary), select the first bone I extruded, switch to Pose Mode; and when I try to set the constraint in the Object Constraint tab, same error message.

This baffles me : (

(Fikcio) #4

Okay, never mind. There’s a Bone Constraints tab; I was trying to set the constraint in the Object Constraints tab : P


(Arx) #5

I got stumped on this one too.

Thank you very much for actually actually including the details on how you solved it.

Hopefully they will remove constraints from the modes in which they can’t be used, or at the very least, change the error to point you in the right direction.


Shift + i = Constraint inverse kinematic

then go into pose mode to make sure you apply the constraints , Also make sure to select the end bone then the actually IK bone you wish to have as the IK then do Shift + i .

that will set the first selected bone as the target and the set armature of the target as well then the second bone as the actual IK. Lastly, go back and add a pole bone so the IK can point in the same direction of the pivot point of the new bone added and set that bone armature as the pole armature.

(cgCody) #7

While new folks looking to help others out are always welcome around here, I’m thinking the OP figured out his problem at some point between now and the last decade. :smile:

(Clockmender) #8

I think you mean “set that bone as the pole bone” and yes, as my friend @cgCody suggested, you are a little late with this reply… :smile:

Cheers, Clock.


I just joined the community last year. lol so yes, I should of joined years ago. but felt no need to at the time.