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The I-beam will be right below the 2x10 SPF joists on 16 inch centers which are spanning 14 feet.
I am planning on fastening the I-beam to 7 joists using 2 lag screws per joist. The load will only be able to travel the middle 96 inches of the 10 foot beam.
Thanks for your link Old Tele man. According to that, the maximum
direct withdrawal load of a 3/8 lag screw penetrating 3 inches into the side grain of SPF would be:
8100*0.42^1.5*0.325^0.75*3 = 2847 pounds
So I don't need to worry much about the 14 lag screws not being able to handle half a ton. Even with the load 12 inches from the end of the beam I'm looking at a safety factor over 10.
Each joist is able to support over a thousand pounds of live load. I know this is for a distributed load, but since I span seven joists with the beam and the trolley will not travel to the very end of the beam, I'm not worried either.
I was just wondering about the torque. I will do as suggested, make a test connection and go with 75% of stripping or breaking torque, whichever comes first.
Ryland, lag screws can support greater tensile loads than shear loads.
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