Try moving the object origin to one end of the cylinder: Press TAB key to enter edit mode. Select all the vertices on only one end of the cylinder. Click Mesh->Snap->Cursor to Selected. Press TAB to exit edit mode and return to object mode. Click Object->Transform->Origin to 3D Cursor. Now when you press S to scale (and then Z to constrain the scaling just along the object’s z-axis), the object will “expand” out from the new object origin on the end.
You could also put a hook on the mesh vertices at one end by selecting them and pressing CTRL-H, but then you would move a hook (empty object) instead of using the scale operator.
Yep that did it. You must have been beaming a signal right at me. I was just in Blender doing that exact same thing. Setting the orgin. I came over to delete post or update it, since I do not know how to delete a post. And there you are with the answer. Thank you! I do not know of Hook… But I will write it down and look it up.
Peace