If a lag screw with a 5/16-inch shaft is installed correctly, it can withstand pull-out, or withdrawal, of up to 212 pounds in close-grain hem, fir and redwood, and up to 266 pounds in larch Douglas fir, according to information from the American Wood Council.
Then, how much weight will a 1/2 lag bolt hold?
2 Answers. Shear strength of the hardware isn’t going to be a real concern. A single 1/4″ Grade 5 lag bolt, in a configuration like this, will fail at roughly 13,000 lbs. Even 1/8″ lag screws (well down into “numbered” screw sizes) will have a shear strength of over 3,000 pounds.
Subsequently, question is, how long of a lag bolt do I need? You will usually need to pre-drill a 5/16” pilot hole into the rim joist if you are using ½” lag bolts. Your bolts or screws should be long enough to extend at least ½” past the board you are attaching to. They are usually installed in a zig-zag pattern.
Also to know, how much weight will a bolt hold?
bolt could hold 70,000 x 3.14 x (0.3^2)/4 = ~5000 lbs.
How much weight will a 3/8 lag bolt hold?
The pull-out value for a 5/16″ lag screw in most lumber is something over 100 pounds per inch of thread. Increasing to 3/8″ puts the value over 200 pounds per inch of thread. So, if you use even a 5/16″ screw with two inches of thread in, you could hang the entire projector off one lag.