http://www.infiniteyarns.com& this is a ball winder
if you put a skein of yarn on the umbrella swift & then attach the yarn end to the ball winder, you can wind a loopy skein of yarn into a tidy little package to knit with.
this assumes you can get everything hooked up properly:
1) untangle & twist the skein of yarn into a big loop of yarn.
2) take this big loop & get it up onto the umbrella swift, which requires the successful completion of 3 additional tasks that are too complicated to write about here & coordination i do not have.
3) extract the yarn end. no-- extract the correct yarn end. there are 2 yarn ends & if you pick the wrong one, you get spaghetti. spaghetti requires spending an hour on the floor to untangle by hand.
4) figure out which direction the yarn end goes through the double-looping thing on the ball winder.
i fear this contraption because i get spaghetti maybe 75% of the time & i cannot begin to tell you how embarrassing it is trying to get spaghetti off the umbrella swift in the middle of a busy yarn store.
the woman in the store got me started with the first skein. everything went fine, but then i had to do a skein all by myself. i was dealing with this for 10 minutes. i finally got the skein up onto the umbrella swift & set about extracting the correct yarn end. it took me forever to find any yarn end at all & i was so happy when i did that i just assumed it was the correct end. but of course it wasn't & i got spaghetti & had to spend another few minutes trying to get the spaghetti off the umbrella swift & the whole mess stuffed in my bag so i could get the hell out of there.
tonight i spent an hour on the floor untangling spaghetti.
