It depends on what type of wood you are using as well. There are some types of wood that I can't scrape without tearing, although it took me a long time to realize it. For example, I can't scrape chinese elm. When I work with it, I have to focus on using the gouge(s) with very accurate and proper cuts. Take your time and get to know the wood you are working with, and remember that every cut you make can be seen as practice for the end product. You should be able to take many, many cuts on a bowl before you are finished...use them as practice to get the best surface possible by taking your time and turning off the lathe often to examine your work. You can even try scraping the wood long before the bowl is close to completion just to find out what techniques are going to work for you on that particular pice of wood.