Hemp string for tying packages for posting comes in various thicknesses and can usually be found in hardware stores, the post office, possibly by questioning Google or e.Bay. If you coat a length with PVA glue (woodworking glue) you can paste down any "fluff" and also roll the string to the finished shapes that you want it to end up as, while it is still wet. PVA dries clear, so if you want to paint the string to a different colour, you can easily do that afterwards
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