How much fondant icing do I need?

[Ireallyshouldchangemyusername]

Making toddler's birthday cake. It will be 3 x 7 inch square cakes, probably trimmed to make them 6 inch and probably layered 3 high... Want to make a cuboid so height will depend depend on the exact bake.

Calculators online give what seems to be an insane a estimation. I covered an 8in round tin with 500g marzipan the other week. I would have thought 1kg would be needed as there will be 4 sides of the squares not needing covered, as they will be hidden in the cuboid.

Hope this makes sense.. If you have got this far please share your wisdom!

TIA

I am a bit lost to be honest! What sides are not being covered? Is it just going to look like a box, if so there are 4 sides and a top roughly 7x7 to cover, is that right?

If that is what you are doing then the amount needed varies by how thick and how good the fondant is, I couldn't imagine using more than 1 kg for that but I roll thin and I would be panelling a box shape rather than rolling a circle as the circle would need to be 21" across so lot of wasted space when rolling and need enough to roll that size even though not all used up.

Sorry if I have totally misunderstood your query :)

Hi. Thanks for replying

So it will be approx 7 x 21 x 7 inches. A box shape but not covering the base, so 2 7 x 7 panels for the ends and 3 7 x 21 panels for the sides..

Sorry for the confusing first post.. I got myself in a right muddle.

Thanks for your help!

ok so a big rectangular box if I am picturing right, that sounds huge! So you need 3 strips of 21"x7" for the top and two long sides and 2x7"x7" pieces for ends. I'd say you'll need more than a kg for that, are you buying like a Tesco 1kg pack for example, I'd be buying 2 anyway, you'd never roll it out to that size, that's practically at a rough calculation a 2ft square piece of rolled fondant you need, no hope would 1 kg roll to that size at any useable thickness.

Ah ok
Yeah, it is huge.. My oh thought it would look better to make it deeper. Which i do agree with, but it's just too big I think. I think i will make it 5 x 15 inches. There will be a crown thing on top too.. It's a number 3 numberblock. Really easy as just 3 cubes but it's to feed at least 40..... Though I don't want much waste.. Think inwill do the body in 2 layers and then arms and legs as 1 layer of cake... Some people use fondant to form arms and legs but it's so expensive for coloured stuff especially

You need loads more fondant than you think you will. Because if you roll it too thin, it will crack/tear as you try to put it on.

I'm not sure what the format of your 3x7 cubes will be but I recently covered a 12 inch cake board with fondant and it needed 1kg

Sorry just seen you're doing 3 x 7 inch cubes stacked. You'll need more than 1kg. I'd buy 3kg to be on the safe side.