Counterwinding is merely the process of winding the thread back to the point where you started your hackle and then forward again to the head of the fly. You want each turn of thread to go over the stem of each turn of the hackle to bind the stem down.
You do your counterwind in the opposite direction to that of the hackle.If you wound the hackle clockwise wind your thread counterclockwise. To start winding the thread you must first apply one or two half hitches this locks your thread so you can counterwind without the thread loosening.
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