I have the malone kayak carrier and with how the kayak slides up the back of the car, the plastic from the carrier keept rubbing off on the bow of my boat leaving black lines of plastic on the gelcoat which are difficult to get off. I’ve since covered the plastic with athletic tape so it no longer rubs, but I can’t figure how to get the plastic off which has already rubbed onto the boat. I am unsure solvents will be enough for this, what solvents and abrasives are safe for the white gel coat?
I used a small amount of gasoline on a rag to clean plastic marks off the side of a van when it rubbed another car’s black bumper cap. Gas won’t / should not hurt gel coat.
Just be sure to clean the area well afterwards.
A buffer with rubbing compound will probably not work well and will be more aggressive for use on gel coat than necessary. When trying to remove plastic residue with a buffer it will likely just smear on the boat and clog up the buffer pad. Acetone or similar solvents will probably work just fine. After removing the residue treat the hull with a UV protectant like 303® or a good marine wax.
Actually, they don’t have any abrasive in them at all; it’s just the nature of the melamine material that creates the abrasive effect. It’s millions of tiny edges of the cells in the material that do the work. It’s pretty amazing that they clean really well, but can be used on surfaces like latex paint without causing damage. The only downside I’ve found to them is that they’re not durable at all.
Yikes. I’m surprised (but not really) about some of the answers here. If it’s only plastic or rubber from a kayak rack, there is zero need to use anything abrasive, a power tool or a carcinogen. Likewise you can use Acetone but be aware that acetone is a solvent and is removing a small amount of gelcoat every time it is used. You may not ever notice how much it removes, but it is, and I want to preserve the finish on my boats as best I can. What you really want to use is denatured alcohol. It will take rubber and plastic off with the slightest elbow grease. Follow that up with some StarBrite hull cleaner (available at Worst Marine etc.) to remove any brown stains on the hull from dirty water. Starbrite is a godsend in that regard. It easily takes off brown water stains that soap and water will not.
Denatured alcohol is always my first chemical of choice for cleaning (if water fails), as it’s pretty benign. Mineral spirits (a.k.a. “paint thinner”) is the next choice, as it’s more effective in some cases, but won’t damage most surfaces. If that fails, lacquer thinner or acetone would be the next step, but they will damage many painted surfaces and plastics, so you have to be judicious with them. A natural alternative would be a citrus cleaner, but they can also damage paint and plastics.