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Using locking pins to mark the end of the cast on on the yarn tail and the yarn coming from the ball
Pattern Tailor

LTCO (Long-Tail Cast On) Calculator

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  • LTCO Calculator Pattern Tailor

Description

Using the LTCO (long-tail cast on) requires a long tail.  How long?  Let the LTCO Calculator tell you.  No more coming up too short, or too long tail because you just weren’t sure. This is a Goldilocks tool: you can get it just right!

Go here to practice the LTCO if you are not already familiar with it.  There is a video.

Use locking markers that are different to mark the three positions you are marking below.

Casting on and Marking for the LTCO

  1. Put a marker into the yarn where the yarn for the first cast on goes over the top of the needle OR if you use a slip knot, place a pin at the base of the slip knot on the yarn coming from the ball (the slip knot will not be counted as one of your cast on stitches.
  2. Be sure to have the tail at the front.
  3. Cast on 10 or 20 stitches using the LTCO.  If you are doing something under 100 stitches, cast on 10.  If you are doing something longer, cast on 20.
  4. Put a pin marker in the yarn tail after making the last cast on, as close to the needle as possible.
  5. Put a pin marker in the yarn from the ball, again as close to the needles as possible.

Take the needle out of the cast on.Using locking pins to mark the end of the cast on on the yarn tail and the yarn coming from the ball

Measuring Your Cast On Yarn Consumption

You will have two markers showing the ending of the cast on, one on the tail and the other on the yarn from the ball.  Undo the cast on by gently pulling on the tail and yarn while holding onto the middle marker.

  1. Measure between the two end markers to get the total length of yarn used.
  2. Measure from the tail end marker to the middle marker. This is the length of yarn used on the bottom needle.
  3. Do the same from the yarn end marker to the middle marker. This is the length of yarn used on the top needle.

Now you can go to the Pattern Tailor and find out how much yarn you need for your long-tail cast on.

Sizes

N/A

Gauge

N/A

Needles

Use needles to match your project!

Supplies

Three locking markers that are different.
Tape measure or ruler.

Yarn

Your choice!

As Shown

I used DK yarn and US size 4[3.5mm] needles for my photos.

Techniques Used

flexible long-tail cast on
Long Tail Cast On
slip knot

LTCO: Marking the center of the tail and yarnLTCO: stitches taken off the needle with end of cast on and beginning of cast on marked with locking pinsUnraveled LTCO laying on ruler to measure length of the tail and of the yarnAfter unraveling the LTCO, 3 pins mark ends and center

LTCO Calculator Pattern Tailor

Here’s a User’s Guide for the LTCO (long-tail cast on) Calculator.

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