I'm with Tim and Warren on this one. A short section of straw over the bobbin can be a real help. I've collected a variety of sizes from the various fast food places over the last several years. My wife thought I was crazy when I was putting a half dozen straws in my pocket every time we went out to eat.

It's just possible she right about the crazy part but the straws work well for keeping hackles out of your whip finishing. A good, no cost trick worth trying out.