I checked the forums using the search function and didn't find this answer so I'm posting it to you experienced decorators.

I'm making sample cakes for the store I teach at.

The 2 I've already done I did completely from royal icing as they were mples of buttercream techniques. The problem is that only after 1 month, the colors are fading a lot and I can't get the dust off easily.

What can I do to the dummy cake covered with royal icing to preserve the colors and make it easier to dust? I'd like to get a 4-6 month shelf life if that is possible.

Does anything need to be done to fondant to preserve color and make it dustable after it's well dried?

Thanks in advance.

This may be a bad answer, but the dummy is never going to be edible, so I would use some ficative from the fine art section. It places a sort of acrylic barrier between the surface it's sprayed on and the environment. Its purpose is to help prevent smudging and fading of art pieces, so I'd think it would work on fondant, too.

Not a bad answer. Just wondering if you have ever used it on royal icing. Does it have any bad reactions?

What about a clear paint sealer from the hardware store? I don't want to use something that will eat the royal icing after spending a couple of hours working on the display.

I have not actually done a dummy cake yet to use it on. I have, however, used it on paper mediums, polymer clay, foam core sculpture, wood, and assorted other artistic surfaces with no ill effects. If you get matte finish, it won't even make it shiny.

And fixative IS a clear paint sealer. It's just an aerosol form of it. The photo fixative in particular is specifically formulated to be nonreactive to avoid destroying the chemical reactions that have gone on in photographs. (Non-photo fixative, such as workable fix, can sometimes cause photos to turn yellow.) That might be your best bet.

. . . you may want to consider Perma Ice for future dummies . . . http://www.countrykitchensa.com/catalog/product.aspx?T=1&productId=1717

You can also use lightweight spackling. If you are going to use royal flowers on it make sure the spackling is good and dry BEFORE putting the royal icing stuff on it. (learned that the hard way) It is pretty easy to use, I even smoothed it with Viva before it was completely dry and it worked out great. (and if you can't get it smooth, you can sand it when it is dry!!)

You can also use lightweight spackling. If you are going to use royal flowers on it make sure the spackling is good and dry BEFORE putting the royal icing stuff on it. (learned that the hard way) It is pretty easy to use, I even smoothed it with Viva before it was completely dry and it worked out great. (and if you can't get it smooth, you can sand it when it is dry!!)

I have to agree on using PermaIce. It's specifically made for cake dummies and is easy to dust. Although you can't use food color to tint it, you can use the dyes made for PermaIce.