Another thing about draw knives, get one and use the same one over and over and over until you can make it work the way you want it to, this take a bunch of practice. No one gets the hang of proper draw knife usage right away, it takes time.
I was teaching a friend how to chase a ring last year, he spent 2 hours sweating and cursing to do half the stave. I gave him a break and finished the rest of the stave in less than 5 minutes. After working on hundreds of staves and billets with the same draw knife it has become an extension of my arms. I can get the exact cut I want without thinking about it, like I said, practice, practice, practice.