Has any one used Y10 to clean the inside of their boat?
this be the stuff
I've always used oven cleaner or G6 polish on rust/stubborn stains with good results.
Y 10 certaily works on rust stains on dacron sails - eventually - the oxalic acid is very dilute so it doesn't harm the cloth but it can take more than one application. I used it a couple of years ago to improve the look of a few older sails that I got with my first Merlin.