sizing through tenon help needed

[Michael Hammers]

I posted this in another forum but thought I would try here to see if anyone had any experience with this.

I have glued up my legs and have my stretchers ready on my bench.

My base posts are 3 3/4" thick and 5" wide.

The stretchers are 2 7/8" thick and 6" wide.

So here is my dillema. I want to make a tusk tenon. With a total thickness of 3 3/4" I need to create the shoulder and through piece.

In rules of thirds this would mean the shoulder would be 1 1/4".

So that being the case I would have to again split this in thirds to determine the tusk size which in turn would be close to about 1/2".

Does this seem right? I am worried I do not have enough material to make a viable and strong joint.
__________________

[Jamie Buxton]

Those are pretty massive hunks of wood. You have plenty of meat to do anything that looks good, and the structure will be solid.

The shoulders don't need to be anywhere as big as you're making them. A half inch would do just fine. That still gives you lots of bearing surface, and lots of post width going past.