Section VII
No. 8
This scale provides a means of weighing propellant and other items when conventional scales or balances are not available.
MATERIAL REQUIRED:
- Pages from Improvised Munitions Handbook
- Straight sticks about 1 foot (30 cm) long and 1/4 in. (5 mm) in diameter
- Thread or fine string
PROCEDURE:
1. Make a notch about 1/2 in. (1 cm) from each end of stick. Be sure that the two notches are the same distance from the end of the stick.
2. Find the exact center of the stick by folding in half a piece of thread the same length as the stick and placing it alongside the stick as a ruler. Make a small notch at the center of the stick.
3. Tie a piece of thread around the notch. Suspend stick from branch, an¬other stick wedged between rocks, or by any other means. Be sure stick is balanced and free to move.
NOTE: If stick is not balanced, shave or scrape a little off the heavy end until it does balance. Be sure the lengths of the arms are the same.
4. Make a container out of one piece of paper. This can be done by rolling the paper into a cylinder and folding up the bottom a few times.
5. Punch 2 holes at opposite sides of paper container. Suspend container from one side of stick.
6. Count out the number of hand¬book pages equal In weight to that of the quantity of material to be weighed. Each sheet of paper weighs about 1.3 grams (20 grains or .04 ounce). Suspend these sheets, plus one, to balance container on the other side of the scale.
7. Slowly add the material to be weighed to the container. When the stick is balanced, the desired amount of material is in the container.
8. If it is desired to weigh $ quantity of material larger than that which would fit in the above container, make a container out of a larger paper or paper bag, and suspend from one side of the stick. Suspend hand¬book pages from the other side until the stick is balanced. Now place
a number of sheets of handbook pages equal in weight to that of the desired amount of material to be weighed on one side, and fill the container with the material until the stick is balanced.
9. A similar method may be used to measure parts or percentage by weight. The weight units are unimportant. Suspend equal weight containers from each side of the stick. Bags, tin cans, etc. can be used. Place one material in one of the containers. Fill the other container with the other material until they balance. Empty and refill the number of times necessary to get the required parts by weight (e.g., 5 to 1 parts by weight would require 5 fillings of one can for one filling of the other).