Long Tail Cast On

The Long Tail Cast On is one of the most popular cast ons. It’s a little tricky to learn, but it is perhaps the fastest cast on once you get the hang of it.

This tutorial is designed to help you fully understand the long tail cast on. Therefore, there is a lot of information in it. Click here if you’d like to jump straight to the video.

Anatomy of the Long Tail Cast On

This cast on is unique in that it actually combines two techniques: the Backward Loop (or Thumb) Cast On and knitting the first row. That’s right… you actually cast on and knit a row with this cast on. Therefore, if the first row of your pattern is knit, you can skip it and go directly to the 2nd row. If you are working in the round and the first row is purl, you can skip it and go to the 2nd round. Don’t get hung up on this – in most patterns it won’t make a noticeable difference if you skip the first row/round or not.

Now, I rarely use the Backward Loop Cast On because it is weak and sloppy. However, when incorporated into the Long Tail Cast On, it is neat and sturdy because instead of looping around the needle, it is just looping around the working yarn. 

You could replicate the Long Tail Cast On by doing a backwards loop cast on with a needle that is about the same size as your yarn and then purling the first row. But who wants to go through all that hassle when the Long Tail Cast On gets it all done in one fluid motion?

The reason it’s called Long Tail Cast On is that it requires a long tail of yarn to complete it. You use both the tail and the working yarn to knit this cast on.

Estimating the Tail Length

One of the most frustrating things about the Long Tail Cast On is estimating how much of a tail you need to complete it. Unlike the Knitted Cast On or Cable Cast On, you actually use the tail as part of the cast on – and if you make it too short, you’ll have to rip it out and start over. If the tail is too long, you waste yarn.

If you Google Long Tail Cast On, you will find a lot of methods to estimate how long to make your tail. One of the most popular is to wrap your yarn around your needle 10 times (which simulates 10 stitches), then measure how long that yarn is and use it to estimate how much yarn you’ll need for your tail. 

But there’s a problem with this method. When you do this cast on correctly, the tail yarn is not wrapping around your needle. It secures your working yarn, and travels beneath the stitch (and needle) to form the cast on edge.

So… the length of the tail depends on the thickness of the yarn you are using, not the size of needle.

How to Estimate Your Long Tail Length

The best method for estimating your tail length is to:

  1. Use a slip knot to start and cast on 10 stitches using the long tail cast on (11 stitches counting the slip knot)
  2. Grasp the tail yarn at the end of the last stitch and don’t let go
  3. Rip out the cast on except for the slip knot
  4. Measure how much of the tail yarn was required for those 10 stitches

Use that to estimate how long your tail needs to be. Remember to add at least 6” so you have enough tail to sew in when you are finished with your project.

So to determine the tail length:

Multiply the number inches used for your 10-stitch cast on by the number of stitches you need to cast on. Then divide that answer by 10 and add 6.

The formula is: 

Yarn tail length =([# inches used for your 10-stitch cast on] x [the # of stitches you need to cast on] / 10) + 6”

I recommend you add a little to this measurement – especially if you have to cast on a lot of stitches. It’s more frustrating to rip out and reknit 100+ stitches than it is to waste a foot or 2 of yarn.

Slip Knot or Not?

I tend to avoid knots in my knitting as much as possible. Therefore, I rarely use a slip knot for any cast on, including this one. It’s really a personal preference, and using a slip knot will create a more well-defined corner. But my thought is that there is no slip knot on the other end of the row, so why have one here? Again, personal preference…. I’ll show it both ways in the video.

Holding the Yarn Properly

Regardless whether you knit Continental style (holding the yarn in your left hand) or English style (holding the yarn in your right hand), you will hold the yarn in your left hand for the Long Tail Cast On.

When you hold the yarn, you want the tail to go over your thumb. Holding the yarn backwards will not affect the appearance of your cast on. However, holding the yarn properly is important for 2 reasons:

  1. Consistency… If you estimate your tail as described above holding the yarn correctly, then do your actual cast on holding it backwards, you will run out of yarn.
  2. When casting on a lot of stitches, the yarn around your thumb has a tendency to untwist. Having the loose tail (rather than the working yarn attached to the ball) around your thumb makes it easy to drop it and allow it (or force it) to re-twist.

How to Knit the Long Tail Cast On

There are 2 ways to do the Long Tail Cast On: The Sling Shot Method and the Thumb Method. I prefer the Sling Shot method because it is fluid and fast. That is the one I’m going to demonstrate in the video. It is similar to playing Cats Cradle (you remember that from your elementary school playground, right?). You may need to practice it a few times to become comfortable with it, but when it “clicks”, you will find it fast and easy.

Tips for Knitting the Long Tail Cast On

  • To maintain consistent tension and to avoid an overly-tight cast on, ensure that each new stitch is on the shaft of the needle, not on the point. 
  • Snug each stitch, but don’t pull them tight or bunch them together tightly. Your cast on should be fairly stretchy and easy to knit. If it’s not, you are tightening your cast on stitches too much.
  • If you have loose loops of yarn around your needle, you are doing the cast on incorrectly. Each stitch should be secure.
  • This is the method for doing the Long Tail Cast On knitwise. It is also possible (but much less common) to do it purlwise.

How to Ensure You Won’t Run Out of Tail

If you are casting on a lot of stitches and don’t want to have to estimate how long to make the tail, you can use 2 balls of yarn – or both ends of the same ball – to do the Long Tail Cast On. In this case:

  1. Leave at least a 4” tail on both yarns and tie a slip knot with both yarns held together.
  2. Do the cast on with both working yarns. Do NOT count the slip knot as a stitch.
  3. When you are finished casting on, cut one of the yarns, leaving a 6” tail.
  4. Begin knitting with the uncut yarn. When you get to the slip knot, drop it off your needle and pull it out.

The disadvantage to this method is that you have 2 more tails to sew in. 

You can also use this method to do a two color cast on by simply using two different colored yarns. If you follow the instructions in this tutorial, the cast on edge will be the color on your thumb and the first row will be the other color.

A more advanced technique is to use the knitwise and purlwise methods together to do a two color cast on. This will produce a cast on where every other stitch is a different color.

Other Names for the Long Tail Cast On

Like so many knitting techniques, this cast on is sometimes referred to by other names. The two most common are the Continental Cast On and Slingshot Cast On. Other less common names include: Double Cast On, Two-Tailed Cast On, Knit Half-Hitch Cast On, German Cast On, Finger Cast On, Y Cast On, Two Strand Cast On, One Needle Cast On, and Single Needle Cast On.

Because I like consistency, I encourage you to use the most common name: Long Tail Cast On.

Want to Practice the Long Tail Cast On?

Our Brady the Snowman Knit Along is a fantastic little project for practicing this cast on, as well as the Tubular Cast On. The Long Tail Cast On is used for the snowman and the Tubular Cast On is used for the hat. Check it out at https://knitalongclub.com/course/brady/.

Brady KAL

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