Shellac flakes are the base for the coating of your rabbits in your window sash. It is important to trap the raw linseed oil in the linseed oil glazing between the shellac and the organic linseed oil paint on the outside of the glazing. This is why old linseed oil glazing last for 50 years.
 
Mix the shellac flakes with just a few drops of denatured alcohol. The mixture should be of the consistency of syrup. With thick shellac you will only need one coat. Drying time is one hour.
 
Shellac is an excellent barrier. Shellac is also used for knots to prevent the sap from going through any paint. Visit www.solventfreepaint.com for more about linseed oil products.