used the West marine repair kit for a chip on the transom made by the bow fitting of my dinghy. The chip was the size of a dime and about 1/4 " deep. The job is not that great,however I don't know if it is my poor technique or the repair materials. I think a mthicker putty-like material that would not run on a somewhat vertical surface would be a better choice in my situation. It's also very hard to match the color even in my case with a white hull.