I am making my first 2 tier cake, sponge cake bottom is 9" top is 6". Will i need to support this or will they be ok just on top of the other?
If i do need to support it with dowles shouldi put them in before i ice the cake or after through the icing?
for every 4" of vertical height you need support. So, yes you have to put support in the bottom cake to, err . . . support the upper tier.
Ice the bottom tier then put the support in.