When knitting intarsia or fair isle, yarn bobbins are used to hold a small amount of yarn without getting tangled.
They're commercially available fairly inexpensively, but I never have one around when I need it. Additionally, it's 102 degrees Farenheight out today, and I have no interest in leaving the house in search of one. So I printed it!
It's sized for worsted weight yarn, so if you're working with something thinner you may want to make the notch on the top a little narrower. Alternately, you can print it as-is and smoosh the tang in a bit while the plastic is still hot.
yarnbobbin2.stl |