If I want to make a two teird cake, but not huge. (mainly for childrens parties) What sized tins?

I was thinking 10 inch round on bottom, what size would be good for top?

and for a square, was thinking 10 inch square on bottom, what size would be good for top?

And I would need to put dowelling inside to support the top layer?

Also what is meant by 'daming' when doing the buttercream under the fondant, is that leaving sides and cutting out a groove? (just guessing)

Thanks again!

Hi, and welcome to CC.

I like a 6" top tier on a 10" cake. This gives you a big enough shelf or edge of the cake to decorate. (I have several of these in my pix if you want to see the proportions.)

I always support the top tier- I use straws-and I run a dowel down through the center of the whole cake

A dam is a thick layer of butter cream that is piped around the edge of the bottom cake in a tier before you add the top layer of cake. The dam is supposed to keep the buttercream (or whatever) filling from oozing out between the layers and making a bulge in the fondant.

Good luck, and happy caking. Be sure to post pix!

Everything the Poohsmama said is correct. 4 inches is usually the guide between sizes when doing tiered cakes. However, I have done 2-inch differences when flowers are cascading from the top to the bottom since I didn't need the "ledge".