All Thread

[Meatwad]

Nothing fancy, just your average run of the mill all thread you can find at hardware stores. I assume it is grade 2.

Needing 7/16 size, what is the strength of something like this vs grade 5 and 8?

[NOT]

grade2= weakest;
grade 5= average bolt strength
grade 8= hardened, and highest tensile strength of the 3.

If it is holding together something relatively light, and is not bearing a significant load, then grade 2 will suffice. If there is any weight to it, or if it is going to hold something more than 5-10lbs, then just use grade5. 5 is most likely what your hardware store is going to carry. You will only need to use grade 8 if what your building needs to hold up your house, or your car, or a school bus....... you get the point.




NOT

[Meatwad]

Going to use it to finish the supports for a tower to hold it to the house. Have lags want to use bolts to go through completely and then have 1/4" flat stock to use as a backplate. lags hold good but want the extra strength. Was planning to use grade 8 7/16x8" but its a little hard to come by. All thread would eb the last resort if I cant find them at the machining shop. Everywhere elase stops at 6"

[phatzo]

Meat this is what I do for a living 7/16 x 8 is gonna be difficult and 7/16 standard is only grade 5. Consider changing to 1/2" it will be grade 8 as standard and 8" should be easy to get. Allthread, unless you get sampson rod or some other high tensile rod  will be weak as "wee wee" . Look into socket head cap screws, this is a good way of finding high strength bolts in odd lengths.
http://www.tweedbolt.com.au/
I will be happy to take your call if you want to ring me and discuss but I'm in Australia if you want to take that into account