How to Set Up a Balance Scale

Balance scales are used in classrooms, laboratories and doctors offices. They can calculate the weight of objects by using small weights to counter the weight of an object. Moving the grain and ball poise to the left or right will counter-balance the weight applied by the object. Move the grain and ball poise one notch at a time until the beam pointer is balanced and points to the zero indicator.

Instructions

• 1

  Find a flat surface for the balance scale. Always use a flat surface to weigh objects. Any tilted surface will throw off the scale and won't give you the correct weight.

• 2

  Place the ball and grain poise at zero. This will reset the weight and zero out the scale. The ball poise measures grams in increments of 10. The grain poise is used for smaller adjustments and measures grams in increments of 1/10. Push the poise lock, located on the end of the scale near the beam pointer, in with your hand to lock the grain poise into place. This is only done when resetting the scale.

• 3

  Place the beam on the base, making sure the beam moves freely. Slide the end of the beam into the slot on the back end of the balance scale. The magnets in the slot will hold the beam in place.

• 4

  Align the zero adjusting poise to the zero indicator. The zero adjusting poise resets the scale to start at zero. If the zero adjustment poise is slightly off, the weight will not be correctly measured. Turn the zero adjusting poise located near the balance pan to meet the zero indicator on the balance scale. This is only done during the setup of the balance scale.

• 5

  Test the balance scale to see if it is correctly set. Place a 10 gram weight on the scale. Push the ball poise over one notch to the 10 mark. Observe the scale to see if it reads 10 grams. If not, check the zero adjusting poise to see if the scale reads zero with nothing on it.