Shellac is a timeless wood finish that has been used for centuries, cherished for its natural origin and lustrous finish. Derived from the secretions of the lac bug found in India and Thailand, shellac flakes are processed and sold in a dry form that must be dissolved before application. Here’s a detailed look at what you should dissolve shellac flakes in to achieve the perfect finish for your woodworking projects.
The Solvent: Denatured Alcohol
The primary solvent for dissolving shellac flakes is denatured alcohol. This solvent is ethanol that has additives to make it poisonous and unpalatable, primarily to prevent human consumption. Denatured alcohol is ideal for shellac for several reasons:
- Effective Dissolution: Denatured alcohol efficiently dissolves shellac flakes, creating a smooth and uniform solution without leaving residue. The rate at which shellac dissolves can vary based on the ratio of alcohol to flakes and the temperature of the alcohol.
- Quick Drying: One of the benefits of using denatured alcohol is its quick evaporation rate, which contributes to the fast drying time of shellac once applied. This property allows for multiple coats of shellac to be applied in a shorter time span, making it a favorite among woodworkers who need to complete projects swiftly.
- Non-Water Soluble: Unlike water, denatured alcohol does not raise the grain of wood. This is particularly advantageous when applying shellac as a finish, as it minimizes prep work and maintains the integrity of the wood’s surface.
How to Prepare Shellac from Flakes
Preparing shellac from flakes involves a simple process of mixing the shellac flakes with denatured alcohol. Here’s how you can do it:
- Measure the Flakes: Start by determining the amount of shellac you need. A common ratio is a 3-pound cut, which refers to three pounds of shellac flakes dissolved in one gallon of denatured alcohol. However, for smaller projects, you might mix smaller amounts, like a quarter-pound of flakes in one pint of alcohol.
- Mix with Alcohol: Place the shellac flakes in a container that can be sealed and pour denatured alcohol over them. Seal the container to prevent the alcohol from evaporating.
- Shake and Let Sit: Shake the mixture well and then let it sit for several hours, or overnight if possible. During this time, the shellac flakes will dissolve in the alcohol. Occasionally shake the container to help evenly dissolve the flakes.
- Strain the Solution: Once the shellac has dissolved, strain the solution through a fine mesh filter or cheesecloth to remove any undissolved particles. This step ensures a smooth finish when applying the shellac.
- Application: Apply the shellac using a brush or a spray system. Shellac dries quickly, so work swiftly and use smooth, even strokes.
Tips for Working with Shellac
- Temperature Sensitivity: Shellac dissolves best at room temperature. Cold alcohol can slow down the process, so ensure your denatured alcohol is not too cold before mixing.
- Shelf Life: Once mixed, shellac has a limited shelf life—about six months to a year. Ensure to label your mixed shellac with the date so you can use it within its optimal period.
- Safety Precautions: When working with denatured alcohol and shellac, ensure proper ventilation and avoid open flames, as the fumes are flammable.
Shellac remains a popular choice for wood finishing due to its ease of application, natural composition, and beautiful results. By understanding the correct solvent to use and the steps involved in preparing the finish, you can achieve professional and durable results on your woodworking projects.