well im trying to learn to tie classic salmon flies. i can do a pretty good job with the body and i can do single feather wings, but im having a really hard time with married wings. i can put them together just fine but the trouble starts when i try to tie them down. ive tried the most sensible way i could come up with holding the wing in place, doing a very loose loop around the wing with the thread, then shifting the bobbin to my right pinky and ring finger and then tightening while holding the wing in place with my right and left index fingers and thumbs. but whenever i tighten the thread, something always goes awry with the wing. it'll crinkle up around the tie in point, collapse weird, or something. how do you salmon fly tiers tie down married wings?