I need to be able to support a variable side load up to a maximum of about 250lbs at 10' high. I am planning on using a 14' 4x4 steel pole that will be anchored 4ft in the ground (with concrete). Question I have will 4x4 square pole be good for this application, and would 1/4" thickness would be sufficient? Thicker sidewalls like 3/8 and 1/2" also available but that significantly increases cost and weight. Not really concerned about deflection, but I would not want it to be so much as to cause fatigue over time. Is this straight forward to calculate based on the information above, or anyone aware of rule-of-thumb table somewhere online I can consult for poles?