Yes, you can measure out two pounds of flakes for each gallon of alcohol to make a “2 pound cut”, or do the math for smaller amounts (2 ounces shellac per cup of alcohol in kitchen terms). But it is not really necessary. Here’s the simple, no-measure method I use for mixing shellac.
Start with a tightly lidded jar large enough to mix the amount you need. Mark a “fill line” on the jar indicating how much shellac you want to make. Now mark a line halfway to your fill line. Put in shellac flakes up to this halfway line, then pour in denatured alcohol all the way to the fill line. Screw the lid on securely and shake the mixture frequently – whenever you think of it – for the next few hours. Leave it overnight, stir it well in the morning, and you’ll have ready to use shellac in about a 2 pound cut. If you want it thinner, simply add more alcohol. Thicker? Either add more shellac or just leave the lid off for an hour or so and let some of the alcohol evaporate. You can mix shellac as thick or as thin as you like working with it, and it still forms shellac when it dries.
Want an easier way? Zinsser now sells pre-mixed dewaxed shellac in a 2 lb cut, the ideal for most finishing application, in a format that flows better and has a far longer shelf life (3 years minimum) than what you mix yourself. It is called “Bulls Eye SealCoat.” Now that this has come out, I may never mix shellac flakes again.modest donation to this finishing blog can keep it going to help others. Thanks!