Hello,

I am fairly new to Solidworks so I apologize if this is a dumb question.  Right now I have a thick walled cylindrical tube.  What I want to do is put a hole through the side of the tube, directly in the center.  My question is, how can I set up a reference to make sure it is directly in the center?  First thing I did was make an axis through the center of the tube so I can make sure the hole goes through the center of the diameter, but I still need to center up the hole in the Z-axis or height of the cylinder.

I tried to make another axis by defining it between two planes (the top and bottom of the cylinder), but I got an error that says "Please select two non parallel planes to define an axis."

Hope this makes sense.  I can attach files if need be.