I was wondering if there is a general rule of thumb dimension:

>> For what I've heard described as, "shoulders," (the notch that bears weight from a beam intersecting with a post, for example)

>> For a distance from edge of TF member to pin location, as with kneebraces, etc.

>> And for the difference in span capacity for Timberframe members as a ratio to a 2x, for example. So, if a 2x6 can, "generally," reliably span 8'-0" for roof framing, what could a 6x6, "generally," reliably span?

Of course, these things should be calculated by an Engineer for code purposes, but it would be helpful if anyone can point me towards some basics.

Thanks for any help!