Darren,
All the charts in the world won't make a good machinist. They are for ball park guidance only. There are just too many variables to be put into chart format. Use them only as a rough guide and take it from there.
As Ralph says, sight and sound is the way to find the correct speed and feed, and that only comes from experience.
Start small, and go bigger, not the other way around. You will soon get the feel for it. If the cutter looks and sounds as though it isn't working hard, on the next cut, give it a bit more to do. I will soon show you if you go past what it really wants.
John