What Is a Mc Morran Balance and How-To Use It

Have you ever bought a cone if yarn and are wondering if you have enough yarn to complete your project. A Mc Morran is an easy, handy tool or scale used to calculate the number of yards in a pound of yarn. It consists of a plastic box and calibrated balancing arm.

To use it, follow the steps below.

1. Place the Mc Morran Balance on the edge of a level table.

2. Place the balance arm in the slots on top of the box.

3. Place a length of sample yarn in the notch on the balance arm, allowing the yarn to hang down towards the floor.

4. With scissors, start to trim the yarn length, cutting about 1/2 inch at a time, until the balancing arm is level.

5. When the arm is level, remove the yarn length and measure it against a ruler/yard stick.

6. Multiple the yarn length measurement in step 5 by 100. This number is the yards in each pound of sample yarn. For example, the sample yarn length = 8 inches; multiplied by 100 = 800 yards per pound of yarn.

7. Weight the sample cone of yarn and with a little simple arithmetic, you will have the number of yards on your cone of yarn. From our previous example, the cone of yarn weight 1-1/4 lb. Follow the calculation below.

From arithmetic remember that the part is divided by the whole: part/whole.

Therefore, 800 yards  =  unknown number of yards
        1 pound          1.25 pounds

By cross multiplying: (800 yards) (1.25 pounds)/1 pound = 1000 yards on your 1-1/4 lb cone of yarn

Note: If you are measuring bumpy, slub or a handspun yarn, because of the inconsistencies in the yarn, the measurement may not be accurate but it will give you a yardage approximation.