During our total bathroom renovation project, the new acrylic bathtub wasn't protected properly and this resulted in more than 100 scratches to the finish. Some scratches were deeper than others, many of them longer than 12-14 inches. Sad to say, we had what looked like an old, used bathtub.
After researching ways to remove the scratches, but not further damage the acrylic finish, I decided to try the following technique using two environmentally friendly and everyday household products, with near-perfect results.
To remove the scratches, I used a combination of Crest and Colgate toothpastes and liquid dish soap (I used Dawn). Using a very soft cleaning cloth, I wet the cloth with water and rubbed a small amount of toothpaste into the scratch. I added a couple drops of dish soap and little more water, making a foamy paste and scrubbed the scratches until they began to disappear. It took a bit of trial and error for each set of scratches, since, believe it or not, some of the scratches preferred Crest, others disappeared with Colgate, and a few of them needed a combination of both toothpastes. I also found that for the most difficult scratches, I scrubbed them with the toothpaste/dish soap combination, let it stand for a couple minutes, then returned to scrub again. As I said earlier, this was completely trial-and-error, but since I had nothing to lose, I tried every combination I could think of to remove the scratches without doing further damage to the finish.
Step 1: Scratches Disappear!
I was amazed when I saw the scratches disappearing as I scrubbed with my mixture of toothpaste, liquid soap, and water. After I had happily removed the scratches, I thoroughly washed the bathtub with warm soapy water to remove all of the foamy residue. Except for one very small mark that was deeper than all of the others, all of the scratches are gone.