Hello. i need to make a simple animation of a spinning propeller. However, when i rotate it, it doesn't "stay" in the center, it seems to spin "spiral-like". I hope i made it clear for you :) Please advise. I've posted two pictures just in case.

2nd picture

I can't quite make it out from the picture, since you don't have the group selected in either one, but I would say your problem stems from where the hot point is. You have a propeller with three blades, which means that when you group all your objects together, the hot point will be at the center of the group, but not necessarily the center of the propeller. A good way to fix this is to center the entire group on the origin of the scene (ctrl+shift+o), and then to jump into the group, and find where the propeller head is located. Memorize or (like I do) write down the x y and z locations of it, and then jump back out of the group and in the properties tray under motion/transform tab uncheck "Lock Center and Hot Point". Enter the x y and z into the hot point for the object, and then check "Lock Center and Hot Point". It should work fine then. EMC

thanks! another stupid question - where do i see the coordinates of the object?

Properties tray, they have the X Y and Z coords for the selected object. Both Center and Hot Point are listed. In the middle of this tray, is where you can choose how to rotate the object (it doesn't do the rotation, btw) whether by the center or hot point. If you're moving the hotpoint, do it in the 4-views. it'll be a helluva lot easier.

thanks!