I have an idea that I'm not sure how to execute, thought some of you fine decorators might have the answer!
I'm making a Thomas the train cake next week. My son has the Thomas case for the small trains, this case is about the size I'll be making the cake. I'd like to somehow make a mold of Thomas' face, then when it's dry use it to mold my fondant into the exact shape. Would this work? If so, anyone know how?

Play doh is great for making molds and it's non-toxic.

Try gelatin..make a very dense mixture of unflavored gelatin and water mixture, then submerge the part you want to make a mold, let it set then remove that item..it shouled leave a deep impression..I have seen Pastry Chef Jacque Torres make this.

Couldn't you just use gumpaste (or even fondant) to make the mold? That way you know it's safe.

I've also seen Jacques Torres pack flour or cocoa powder (depending on whether you're using white or dark chocolate) and press the item into the powder. He then carefully poured chocolate into the cavity and let it set. You probably don't want to use chocolate, but if you do this may work.

I have used sculpey clay to make molds it's non-toxic.........once it's baked ...and becomes as hard as plastic and can be washed and reused .........don't use any kitchen utensils on it though because it can be toxic before it's baked.........I have used it to make impressions of rocks for castle walls and brick walls, etc. I never thought of molding a toy!!! It's not very expensive and it's very easy to work with........the cocoa powder and powdered sugar idea will work if you want to make it out of melted chocolate or something liquid, but not fondant