AI'm doing an 8" round 7 layer rainbow cake and in spite of attempting to make thin layers, still ended up with a 7 1/2 inch tall cake. I know I could (should?) have put a board and supports in after 4 inches, but since it's a rainbow cake and each slice is supposed to show all the colors, I didn't put one in. Now I'm nervous about how wiggly it is. Right now it is filled and has just the crumbcoat on. Will it help to put a dowel down the center and in to the cake board? It will be filled and iced with buttercream, with sprinkles on the sides and roses on top.
AYour bottom layer is going to mush to nothing flat. Can you take it apart? If not, fowls into the board to keep it from toppling will not hurt.
ADowels not fowls!
I have done rainbow layer cake much te same as you have - I just inserted 3 bubble tea straws - through all the layers to keep them in place - nothing squished or shifted
If you are using the side sprinkles - its best to to crumb coat and then a thicker layer of buttercream - let it set up fairly firm - you can then roll it in sprinkles in a tray
Thanks for the suggestions! I did put a skewer down the center in to the cake board, and amazingly it didn't settle any more than a typical 4 or 5 inch tall cake. I'll try to post a pic when I can.
AI made the rainbow cake. It was fun to make and every one was surprised when it was cut. I made it as a 6 inch round instead of an 8 inch.