How to clean stovetop grates in bathtub?

Use very hot water, soak in Dawn premium dish detergent for a few hours. I spray mine with frill cleaner and let sit outside in the sun. Then just rinse off.

I wash mine in the dishwasher.

Mine are soaked in the kitchen sink with the hottest tap water you can get, couple cups of white vinegar and sprinkle baking soda on top. Mine only take a 1/4 cup of baking soda as they are cleaned regularly. If really grimy, put in a cup and let them soak for an hour or so.

put a towel in tub so it doesn't get scratched fill with hot water and some ammonia let sit scrub with stiff brush;you might want to use a big plastic tub so it doesn't leave a mess in your bathtub that you'll need to clean next

Put a plastic dishpan in your kitchen sink, unless there's some reason you can't. Cleaning the grates is a chore, and you won't want to be kneeling on the floor by your bathtub to do it.

I use Dawn in hot water for the grates, baking soda for scrubbing them, and a plastic scrubby so they don't get too damaged by scrubbing.

Thank you everyone.👏👏