yarn weights

by Miri
(Florida (U.S.A.))

From what I have read, U.K. 8-ply is the same as U.S. worsted weight or double knit (category 4, medium weight). Baby or sport yarn (also called light worsted, category 3) would be way too fine for a size 10 needle. Medium worsted is the most commonly used yarn over here, and the label generally recommends a size 7 or 8 needle, which takes 18 or 17 stitches to make 4" (36 stitches for 8" on a size 7 needle, or 34 on a size 8). You could use medium wieght yarn on a size 10 needle, but it would be a bit loose. Bulky weight yarns (category 5) usually recommend a size 9, 10, or 11 needle. I have used a size 10 needle with bulky yarn and 32 stitches to make an 8" square. I have also used a size 8 needle and 34 stitches to make an 8" square with medium (worsted) weight yarn.

Also I would like to note that what you refer to as a reef knot seems to be what I would call a square knot.

Hope this helps.