I am stacking a three layer 14 inch square on top of another three layer 14 inch square... so it's two 14 inch squares stacked one on top of another to look like a very tall 14 inch square.

I have those hollow plastic dowels that are about 3/4 of an inch in diameter.

How many should I put in there? They're both VERY heavy cakes. They are filled and iced with ganache.

wow, I usually use 4 dowels "no matter what" but even *I* would change my mind on this one! I'd put 3 rows of 3 .... 9 total.

That is going to be one awesome looking big cake!