I dont normally save the remnants of hackle feathers or other materials but you can save them in a zip lock bag for reuse. The hackle tips can be used a tails on certain patterns, remove the fibers from the quill and the quill can be used as a body material and the webby material at the base of hackle feather can also be used as tailing, wings on midges and chopped up for dubbing.
When using this style of bobbin holder and you are unable to pull thread out of the tube, you will have to adjust the tension by simply spreading apart the arms that hold the thread spool. Don't spread the the arms too far or the spool will spin freely. Just find the right tension for your tying style. Bend the arms until you get it just right.
The bobbin holders shown below have other methods of adjusting the tension on the thread spool.
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