Deflection for a center load on a beam with two fixed / welded supports.
If supports are not fixed, deflection is 4 times greater.
Deflection is directly proportional with the mass.

L = length (mm), W = width (mm), H = height (mm), T = thickness (mm), M = mass (kg)
D = deflection (mm), LM = linear mass (kg/m), TM = total mass for 14 meters length (kg)

Downward mass = 100 (kg)

Steel pipes:
* L = 2000, W = 50, H = 50, T = 2, D =  1.4, LM = 3.0, TM = 42.5
* L = 2000, W = 50, H = 50, T = 3, D =  1.0, LM = 4.5, TM = 62.4
* L = 2000, W = 30, H = 50, T = 3, D =  1.4, LM = 3.5, TM = 49.1
* L = 2000, W = 50, H = 30, T = 3, D =  3.3, LM = 3.5, TM = 49.1
* L = 1000, W = 50, H = 30, T = 2, D =  0.6, LM = 2.4, TM = 33.6
* L = 2000, W = 40, H = 40, T = 3, D =  2.0, LM = 3.5, TM = 49.1
* L = 2000, W = 40, H = 40, T = 2, D =  2.8, LM = 2.4, TM = 33.6
* L = 2000, W = 80, H = 80, T = 2, D =  0.3, LM = 4.9, TM = 69.0
* L = 6000, W = 50, H = 50, T = 2, D = 37.1, LM = 3.0, TM = 42.5

Spruce beams:
* L = 2000, W = 50, H =  50, D =   8.7, LM = 1.1, TM = 15.1
* L = 2000, W = 30, H =  50, D =  14.5, LM = 0.6, TM =  9.0
* L = 2000, W = 50, H =  30, D =  40.4, LM = 0.6, TM =  9.0
* L = 1000, W = 50, H =  30, D =   5.0, LM = 0.6, TM =  9.0
* L = 2000, W = 40, H =  40, D =  21.3, LM = 0.7, TM =  9.6
* L = 2000, W = 80, H =  80, D =   1.3, LM = 2.8, TM = 38.5
* L = 2000, W = 30, H =  90, D =   2.5, LM = 1.2, TM = 16.3
* L = 2000, W = 30, H = 120, D =   1.1, LM = 1.5, TM = 21.7
* L = 6000, W = 50, H =  50, D = 235.4, LM = 1.1, TM = 15.1