Allan- I've got two small pieces of advice to offer which helped me improve the way I was trimming up my deer hair flies. First of all, I only trim with a double edged razor blade now. I was having similar problems with symmetry when I was trimming up using scissors (I believe it was due to the fact that scissors kind of need to bunch up a wad of hair before cutting which I guess is destined to cut the hair to all different sizes). The other thing is the use of a rotary vise helps a whole lot. I've noticed that if i can steady my hand on something and position the blade at the appropriate angle relative to the shank of the hook, I can rotate the fly and shave a nice symmertical shape out of the hair without really even moving the blade. Its probably not the best way to handle it, but it seems to work out well.
Just some ideas! John I am a poor tyer of deer hair flies do to a poor sense of symmetry. After I make my initial trim, I usually find one side longer than the other, and in my efforts to make the other side shorter, it usually ends up shorter than the formerly short side, so I then start trimming on the formerly shorter side which is now longer than the short side but won't be much longer...............I've wound up with some size 16 deer hair flies tied on size 2/0 hooks!
