Claude Dupuis replies: Keeping tools sharp throughout the entire turning of a bowl is important. With some difficult woods I make a cut, sharpen and proceed with another cut and so on. Direction, speed (advancement of the tool) and technique also play a roll. Always have supported grain, ride the bevel and sharpen often. I sometimes resort to a scraper with mixed results. Depends on wood type.
Donna Banfield replies: Some woods are more prone to end grain tear out than others. For example, spalted maple can give some of the best turners a challenge.
First, I use scary sharp tools. That can sometimes mean returning to the grinder every couple of minutes to freshen the edge—and the grinder is never turned off.
Second, I use a very small cutting edge. For me, that means a 3/8˝ bowl gouge with a micro-bevel achieved either by free-hand sharpening the edge or using the Vector system, by JoHannes Michelsen. The difference is a smaller cutting edge making contact with the surface of the wood and taking smaller and lighter cuts. It’s not a race to get to the finish, but getting to the finish with a pretty good finished surface.