I am going to be making a 3 tier wedding cake & I want each tier to be 3 layers. I have never done 3 layers before. Do I need to use dowels or will the 3 layers hold itself?

Basic rule is to use a support system for every 4" of cake height.

If these tiers are to be stacked (rather than individual satellite cakes), of course they'll need support. I'd suggest using a board in the middle at 3 inches.

If separate satellite tiers, you might consider at least using a few skewers to help prevent the 6" tall tier from sliding apart.

Each layer will be 2" inches. Each tier will have a total of 6" of cake with 2 layers of filling.

The dowels will work great & take all the worry out of your mind... With each layer being 2", your cake will be quite high...a support system is recommended...