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Some tips for finer spinning -- adjust your draw-in on your wheel to be minimal, so that you could actually pull the yarn off the bobbin if you wanted to, but it still draws in freely too; use the best prepared fiber you can, i.e. it drafts easily with no sticking or grabby spots; use the highest ratio on your wheel, so you can get twist in quickly.
On a spindle, I typically use a 0.9 - 1.1 ounce spindle for sock yarn singles, and that weight or heavier for plying.
If you have a Louet, one way to reduce draw-in that's fairly specific to them is to "lace" the yarn back and forth between the hooks on either side of the bobbin. This reduces draw-in (it also cuts down how full you can fill your bobbin, though). Louets have hooks on the same "face", so the lacing is all on one side; most other wheels put their hooks on either face, if that makes sense in words ...
For more tips on fine-spinning see How can I spin fine yarn?
As well as several entries on my escapades spinning sock yarn.
I've spent the morning (ok, not all of it!) on flickr looking around at the variety of spinning/knitting groups -- and wa-la, there's one on sock knitting (of course!).
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(yes, it's the same colors as the skein above, but a squooshy 15WPI 2-ply as opposed to the above high twist 18 WPI 3-ply)
And I must-must-must get the socks knit soon, they will be sooo super squooshy.
Teyani (Intrepid Fiber Wizard) has posted a variety of entries on her blog about spinning the sock hop yarns from the Crown Mountain pencil roving (NAJAHC, yadayada), and her instructions were spot-on.
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Ahhhh. It's another skein I'm really, really thrilled with!
Well, now I'll go back to my more factual post-answers mode and stop sharing ;-) just couldn't resist.
I'd encourage folks to put their handspun sock yarn and handspun socks in the flickr group too :-) that way I can have google reader watch it and get my daily handspun sock yarn dose!
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Looking for a place to chat about spinning sock yarn? Here are a few:
on Yahoo Groups: SpinToKnitSocks and sockamaniac_spindle_spinners
on Ravelry: STKS (spin to knit socks)
and I've seen sock spinning questions on Knitty's spinning forum as well as TechSpin (Yahoo Group) and Spin Tech (on ravelry).
Do you know any other places where sock yarn spinning gets discussed? I'm always on the look out for great websites and forums on the topic! Post them on the blog or contact me. Thanks!