Making your own heavy duty fiberglass scouring cleaner is simple and effective. This tried and true old fashioned recipe uses whiting powder, an ingredient commonly used in homemade household cleaners. Whiting is a very fine powder composed mostly of calcium carbonate. As a mild abrasive whiting powder can also be used shine stainless steel, marble, glass, silverware, copper as well as other non ferrous metals. As mentioned, it’s a common ingredient in homemade household cleaner recipes and a little goes a long way.
In a large plastic bowl, mix soap and borax into water until dissolved.
Add whiting gradually, checking the consistency and degree of abrasiveness after each addition. Transfer the mixture into a squeeze-top container, such as a plastic condiment bottle. Repurpose a mustard or ketchup container for this, just be sure to label it well!
Squeeze some of the cleanser onto a damp sponge or lint free cloth and scrub gently. Rinse and dry.