I wouldn't start with fantastic.....it will remove or dull some paints.
I would begin with a dilute solution of dish soap, like palmolive....just a couple of teaspoons in a quart of water.....and spray or dip or dab it on and let it sit for 10 minutes or so.....and rinse it off. Repeat!...And probably again. Have a soft tooth brush handy for cracks and crevasses and some canned air to blow out the water from hidden places and to avoid rust.
Linda C

Thanks so much. I thought dishwashing liquid might be the answer :)

I have a tole topiary lemon tree that gets very dusty. Thank you for the info. I usually bring it outdoors when it's warm and give it a brush with a handbroom or bottlebrush. Now I won't be so afraid to get it a little wet. I've never washed it. :

I have a french tole chandelier that is rusting How can I restore it to it's glory?