well carey it just looks like a squared timber turned 45 ?

Carey,

You being funny? Did someone really ask this?

some people have no common sense petey !

No no no…you’ve got to start with 8”x8” and cut each side to 45°…that yields you a diamond 4x4…everyone knows this…

That's better than a 3 inch chamfer bit in the router

hold the phone RyanGi'
I tried this with a piece of 4x4 I had been keeping for something special, I dont remember what just now, but implementing your process because I wanted t see this "diamond"  ....checking out my now 2x2 It sure just looked like a square piece to me and lots of waste.
Are you sure your angles are correct.
And my piece for 4x4 was already "gold" too!

important note:-
 A "square" has four equal sides and four right 90 degree angles.

 A "diamond" (formally called a rhombus) has four equal sides but its angles are not necessarily right angles. Imagine a square made of straws. If you gently push on the top corner, it tilts sideways. The sides stay the same length, but it becomes a diamond. 

I think that's a myth busted there Mr Mc Ryan

That's crazy!
Just the first cut, tilt the blade or bandsaw table to 45, then the maths say you can rest that cut edge on the table and make 90 degree cuts...

I am sure I set the correct angles !
And I did double check both

Rob

I think her name was plenty.  :)