Shellac's cut

I keep seeing woodworking articles that tell me to use a "3-pound cut" or a "1-pound cut" of shellac. What does that mean, and how do I make it, and which should I use?

Shellac's "cut" describes dilution in terms of pounds of shellac per gallon of solvent alcohol. A 3-lb. cut literally is 3 pounds of shellac flakes or buttons dissolved in a gallon of alcohol—but of course that's a lot more shellac than most of us are going to use any time soon. More practically for many small shops, you can make a 3-lb. cut by dissolving 6 ounces of shellac flakes in a pint of alcohol; a 1-lb. cut requires just 2 ounces of shellac per pint. A 3-lb. cut is quite full-bodied. It's a fairly standard choice for brushing or spraying when you want to build a good wood finish. A much thinner 1-lb. cut is the usual recommendation for use as a fast-drying sandable sealer, or as a barrier or bonding agent between coats of dissimilar finish where adhesion might not be reliable (putting latex over oil paint, for instance). Generally speaking, mix only what you need to use. Dissolved shellac has a useful life of about a year, but dry flakes can be stored almost indefinitely.