Deflection Calculator for Square Tubing
type = steel ends = free
est. weight = 1.7105# per foot
OD = 2" ID = 1.87"
Moment of Inertia = 0.3143
Deflection = 0.9873"
This calculator may give you a rough idea of the deflection of metal tubing, but it's not accurate enough to do any more than estimate it. If the deflection is large enough to permanently bend the tube, then all bets are off.
The steel weights are tweaked for mechanical tubing, and will be less accurate for structural tubing.
The moduli of elasticity used are 29,700,000 psi for steel and 10,000,000 psi for aluminum.
Use at your own risk. Or you'll be sorry.
formulas and data gleaned from: