BayPointArchitect
Sawhorse
After looking at other threads related to screws, I believe that there are those who believe that the performance of a screw is good resistance against pulling out but useless for shear capacity. I admit that I have snapped off a few screw heads myself but I would think that a #8 screw would be worth a very conservative 100 lbs of shear strength regardless of where that screw came from and what it is made of. I have hung more than a few wall cabinets with only two screws and watched people fill up those cabinets with their antique ceramic dishware.
My calculations and assumptions for a #8 screw:
Diameter with threads excluded from the shear plane = 0.164"
Radius = 0.082"
Area in shear plane = pi x radius ^ 2
= 0.0211 square inches
x 36,000 psi
= 760 psi ultimate strength
Fv = 0.22 Fu (coeficient used for bolts according to manual for steel construction - AISC 9th edition)
Fv = 167 lbs shear strength
Am I way off in my thinking?
Thanks
My calculations and assumptions for a #8 screw:
Diameter with threads excluded from the shear plane = 0.164"
Radius = 0.082"
Area in shear plane = pi x radius ^ 2
= 0.0211 square inches
x 36,000 psi
= 760 psi ultimate strength
Fv = 0.22 Fu (coeficient used for bolts according to manual for steel construction - AISC 9th edition)
Fv = 167 lbs shear strength
Am I way off in my thinking?
Thanks