Done some rendering outside, pretty pleased by and large. However, managed to get some gouges in it caused by one of my animals I expect. They are about a few inches long and perhaps a mill deep. I could trrowel on some more render I guess to fill up the scratches but I am worried it'll not look as smooth. Any tips for blending in nicely? I was wondering, for example, if I made up a thick sand/cement "paste" and sponged it in...