Help! I need to make a topsy turvy cake for 150 people. I need help figuring out what size cake pans to use.

Well...I assume you will be using round pans. In that case, there are a few questions. Are you familiar with how each level of a topsy turvy is made (i.e. for a 6" tier- use pans 6", 5", and 4")? Then, how many levels do you want to do, 3, 4, or maybe an adventurous 5 tiers? If doing three tiers, you would need the top of each tier to be 8", 12", and 16". therefore you would use these pans: top tier-8", 7", and 6"; middle tier- 12", 10", 9"; and bottom tier- 16", 15", and 14".

Now when I made my topsy turvy, I made each tier four layers of cake. So I made two layers of the largest size on each tier. Then I sliced one of those layers diagonally and flipped it back over onto itself to create the slant at the top of the tier.

I hope this makes sense...even more, I hope it helps. MAybe someone else knows more and can explain it better.

sorry...that middle tier was supposed to be 12", 11", and 10". Oopsie!

So let me get this right, I need to make 3 different sizes for each tier? I was planning to make it 3 or 4 tiered. This is my first one and I have seen tons of instructional videos. It is for a grad on the 12 of June so I plan to make a practice run.

You stack them on top of each other (smallest on bottom, largest on top) and this makes much less carving for you. You can however change the sizes to suit your pans available. For example, on the small tier, if you don't have a 7" pan, make another 8" instead. Stack the layers with the 6" on bottom. Now when you carve, you know how big the top needs to be (8") and you know how big the bottom needs to be (6"). So just carve down the middle.

Misdawn did a great job of explaining, but just in case you need a picture, try this:

http://cakecentral.com/cake-decorating-ftopict-587795.html