Dummy Cake in Extended Tier

Glue the dummy to your base board, then add the cake tiers on top. You’ll want to put a cake board, slightly smaller in diameter, between the dummy and the real cake. Cover the whole thing with ganache until it’s smooth and seamless.

Personnally I would put the dummy on a board and on the top. Putting it on the bottom would make your cake top heavy and harder to carry. You need to have the wieght at the bottom for it to be stable. Cover the whole cake as normal in ganache. Also if you haven’t covered a barrel before I would read up as much as you can… Are you doing the wrap method?? One more thing. I noticed that you can’t just use glue for sticking polystyrene, it melts it. It must have something to do with the acid in the glue. If you decide to put it on the top just use chocolate as glue.. Good luck, hope it goes well for you.

Securing the dummy to a solid, weighted cake board should eliminate the top-heavy issue. I think it will be much more difficult to ice the cake with a dummy on top as it will want to move around. And to secure it with the center dowel method would likely require two dowels, lest the dummy might spin on just one. It will also be a little trickier to cut and serve.

Fishabel, excellent advice regarding covering a barrel shaped cake. They can be tricky!

Thanks Ladies.
I ganached the cakes last night and won’t be needing the dummy after all, as I did a 7" cake baked in a 6" tin and also for the dome. So after I layered and ganached them it will stand approximately 10" when stacked.
Thanks for the advice on the smaller board between the top cakes, I cut smaller base boards and used those.
For the fondant I’m going to wrap the dome seperately, and then use the wrap method for the bottom stacked cake.
There will be fondant decorations and a strip going around near the top which will cover the join between the dome and cake.
Fingers crossed all goes according to plan.

Glad things are going smoothly so far!