I have to learn how to mix the filler and to get it the correct mix. Too wet and it is hard to sand, too dry and it will not stick. I have learn to mix it into a doe like mixture and it seems to work out OK. I covered the panel ad let it cure. After I sanded it back. All nice and smooth now. I later refilled the pinholes (Thousands of them) I can see I will need a lot of patience and time on this process.