Good morning all. I am new to tying (at about my 6th fly). Quick question if I can describe it right. When I am tying a wing case, I pull the feather toward the eye of the hook. I make 2-3 wraps with the thread, then hold the feather straight up and make 2-3 wraps with the thread to secure the wing case. I cut the feather off. Now when I then go to make my whip finish, the feather as pulled out of the thread. If this is understandable, am I pulling the feather too tight, or not tightening down the thread hard enough or combination of both?