AMaking a 16" round tree stump wedding cake. Plan was to do 4" dummy, then 3 three layer sections (each around 4" tall) . Need 300 servings. Just layered and filled first section. It weighs about 17.5#. So definitely using foam board, bubble straws, and models in those . However, am now wondering if I should sub one of the layers with another dummy? And do kitchen cakes for the last 100 servings? I'm ahome hobby baker doing this for brothers wedding and would rather the cake not implode from the weight. Thoughts? Alternate ideas? Ty!

ADowels not models, autocorrect on phone

ANow I'm thinking a visit to the plumbing section and a bought separator plate. Used a flange and pipe for middle 'dowel'....hmmm

I would think you will be ok... I have seen some huge cakes in the past and they seem ok.

If you use cake board between your tiers and proper dowel and support it should hold its on weight. Make sure the Cake Board is nice a sturdy (a piece of wood would work supper) JUST SUGGESTION:  Home depot has pre cut round butcher block tops (a 20" is less than 30) and you can use it to put cake on. I did that several times looks rustic and makes a nice sturdy cake platter!

 Anyway I think your biggest concern will be lifting and transporting the cake since it doesn't sound like something you will be able to stack on site.

Good luck!

I watch Cake Boss and they use them all the time. :-) Sounds like a good sturdy plan.