Funky Animation Problem

I’m having a strange problem with an animation I am trying to create, involving a baseball bat being swung. The bat moves as expected from the first keyframe to the second and then, for some reason, spins around between that and the third, and then behaves properly from then on.
[video] [/video]

This video is a render of the problem.
I cannot for the life of me figure out why this is happening.

Can anyone point me in the right direction, here?

Can anyone point me in the right direction, here?

A 1 second video clip and not even a blend file to look at ? You need to give more useful info

Perhaps you accidentally rotated it 360° while animating?

I would clear every key-frame and do it again.

I’ve tried clearing the keyframes, that didn’t help. If I had more information regarding the problem I would have posted it, sorry. The video shows the bat suddenly reversing direction between two frames, which is all that there is to see.

I honestly didn’t actually think about uploading the file, but here it is, or a version of it anyway.

Stickman.blend (1.34 MB)

The right hand IK has a copy location constraint to the main bone that animates the bat, the left hand IK is parented to another bone that follows the bat, but I don’t think that has anything to do with the problem.

BTW, Richard, I love the Hartnell Console.

The bone responsible for your grief is “Spine.001”. At the point in which the animation goes bad, simply rotate it back to the correct position.

But this wont fix your issue because blender has incorrectly calculated the motion path because of this bad bone
I find that doing the following helps.

copy the full scene, delete all the frames in the new scene then copy frames from the first scene to the new scene and key frame them. don’t forget to tweak the bad poses before you insert key frame.

Rotating Spine.001 to the correct position just causes the problem to occur later in the animation. I’ll try creating a new scene and everything.

I’d rotated Spine.001 (the bone controlling the bat) 180 degrees around it’s Y axis, so it was flipping it to get to the right orientation. I feel quite stupid now! Thanks to those who helped.