A common method of casting on, also called the “knit half-hitch cast on” or the “double cast on.”
Benefits and Drawbacks
Although popular, this method requires that the knitter estimate the length of the long-tail yarn before the stitches are cast on; if the long-tail yarn is too short, the knitter will run out of yarn with which to secure the stitches before the full number of stitches have been cast on. In that case, the knitter will have to pull everything out, re-position the slip knot to give a longer tail, and begin anew. This situation can be prevented through two methods listed in Variations below.
This cast-on is conducive to picking up stitches on the cast-on edge in order to knit in the opposite direction.
Begin by pulling out a length of yarn approximately three times the desired length of the finished cast-on edge. Make a slip knot at this point and put it on the needle. The yarn attached to the ball is the “working end” and the loose end from the slip knot is the “long-tail end.” Hold the needle in one hand and both ends in the other, with the long-tail end placed in the crook of the thumb and the working end around the first or second finger. Make a half-hitch on the needle with the thumb and the long-tail end, as with the simple cast-on, but do not release the thumb. Wrap the working end around the needle and pull the long-tail end up, over, and off with the thumb, as if to knit. Remove the thumb and tighten the long-tail end around the base of the stitch.
Two different methods can avoid the situation of running out of tail before casting on the desired number of stitches.
One is to use two different yarns, one the main yarn that you are using for your project, and the second a piece of contrasting yarn. Attach the two with an overhand knot and place the needle between the two working ends, with the knot below the needle, and position the working yarn over the top of the needle. Then, using the contrasting yarn as the “long tail” and the project yarn as the working end, work as above.
A second method is the same procedure, only using the two different ends of the yarn ball as the working yarn and long-tail yarn. When finished casting on the desired number of stitches, cut the long-tail end and continue the work from the working end.
The long tail cast-on can also be done in a purl and a twisted stitch version as well.