Hey Bruce,

Just some food for thought. If you are worried about relish tear-out from the thrust of that principal you might be able to create additional bearing surface. That way you would not have to rely on just the tenon.

I have been messing around a little bit cause I have some time. Don't pay attention to that little brace below, that was just messing around, but I haven't completely cast that away as an option some time down the road when the thrust is directed through the tie to the bottom of the tie inside the post.



















If you look closely you can see the bearing surface towards the interior. Of course, every problem has a solution, and every solution a problem.

Also, someone way more skilled and versed than me taught me something when dealing with bearing surfaces in struts. I took this to mean any compression member, like your principal.

It deals with the angle of the bearing surface.


You basically bisect the angle of the rafter, strut, etc. with the tie. I just took the same principal and moved away from the eave line.

Salute,

Mo

forgot to add and it won't let me edit now.

if you do something like that bearing surface, I would leave a little gap between the level line of the rafter foot and whatever is below it (for green wood). that way shrinkage won't lift the rafter of its seat creating an opportunity for shear.