Left side of the blade

[Bill Dufour]

I have not used my tennon jig since I switched from a contractor saw to a unisaw. I hope I do not have to move the guide bar, again.
Bill D.

[Glen Gunderson]

No. If the box is symmetric (that is as long as opposite sides remain parallel while the box is stretched or shrunk in one direction) all the angles will be the same. Only if you make the box more random - opposite sides being different lengths and not parallel, will you get different angles. You can see this very easily if you just imagine stretching a hexagonal box with tools - you could cut it down the middle of any two opposite sides, glue in whatever additional length you need, and you'd have the stretched box without ever having touched any of the angle cuts.

Attachment 382710Attachment 382711

I was referring more to this kind of shape:

box.jpg

That box is symmetrical with parallel long sides and all the angles aren't all the same. That particular one has two 90º angles on the ends and four 45º ones, but the same could apply with various other angles too.

[Steve Demuth]

Got it. Yes, you're right.

[jeffrey bailey]

I worked this up with a piece of scrap and yes all angles are 30 degrees. Now, on to the good stuff.