# How to spin a zig-zag mesh on its axis

I have made a zig zag mesh, and I want to animate the Red & Black section to rotate on its Y axis. I separated the particular mesh section from the rest of the mesh, so it only affects that section which I want to spin. I tried to parent it to an empty object, but its spinning incorrectly. I also tried to reset all transformations but that didn't work.

Here's another example of what Im trying to achieve, the cement truck is spinning the barrel on its axis, so imagine there's 4 of them which spin.

• Can you share the blend file? Aug 16, 2023 at 6:38
• It looks like your segments are not rotation symmetrical, but have an imbalance. Even if you align the empty to the main axis of rotation, you would see the imbalance rotate around. On the other hand, the cement truck barrel is rotation symmetric. Is that your problem or is the imbalance tolerated? Aug 16, 2023 at 8:49

You can use the Hook Modifier.

If I am right, those are not cylinders,but something more like this:

And if I understand correctly, then yu simply want to rotate this shape as if it were a cylinder rotated about it's local axis. You can use two empties as hooks and use a driver to control the X rotation of the one of the hooks.
Each hook will be assigned to the respective side.

• This could do wonders indeed. I merely explained it with cylinders to explain rotation on local and global axis. Aug 16, 2023 at 11:32

What you want is rotating a rotated cylinder along its local axis.

To be able to do so, you shouldn't apply rotational transforms.

In this picture, the left one has been rotated 15° and had it applied, the right one was only rotated.

Suppose I now rotate both 180° along their local x-axis, only the right one will rotate correctly, the one which doesn't have the previous rotation applied.