It is generally not a good idea to scale a recipe up or down by more than 3 or 4 times.
Liquid Measurements
In the United States, liquid measurement is not only used for liquids such as water and milk, it is also used when measuring other ingredients such as flour, sugar, shortening, butter, and spices.
Dry Measurements
Dry measurements are not typically used in U.S. recipes; dry measurements are used mainly for measuring fresh produce (e.g. berries are sold by the quart, apples by the bushel, or peck). Do not confuse dry measure with liquid measure, because they are not the same.
Liquid Measurements vs. Dry Measurements
The table below shows the differences between dry measurement and liquid measurement.
Weight
The two most commonly used units of weight (or mass) measurement for cooking in the U.S. are the ounce and the pound. Do not confuse the ounce of weight with the fluid ounce, because they are not the same; there is no standard conversion between weight and volume unless you know the density of the ingredient. To make matters worse, there are different kinds of weight measurement; Avoirdupois weight, Troy weight, and Apothecaries weight. In the U.S., when someone refers to pounds and ounces of weight (especially in cooking) they are usually referring to Avoirdupois weight.
Basic Cooking Rule:
16 ounces = 1 pound