I am working with a metal surface that has some scratches to it and I need to make it smoother (fill those scratches) with some kind of sealant that will be smooth and not come off due to temperature or water contact. I worked with a gas fitter a few years back, and I know about hawk white, but from what I remember of it that probably isn't what I need this time. Is there any other sealant or glue that would fit that bill??