How To Shellac Musical Instruments

Learning how to shellac musical instruments can help maintain the natural beauty of the wood and the intrinsic value of the instrument. Musical instrument makers have long been held in high esteem for creating works of art from wood that not only are visually aesthetic but functional as well providing untold hours of enjoyment whether listening or playing. The most popular application for using shellac on musical instruments is called “French polishing.” Here’s how it’s done.

Materials Needed:

•Soft cotton application cloths
•Rubber sanding block
•Square wood block
•Small squeeze bottles for oil, shellac and alcohol
•Fine-grained pumice
•Salt shaker
•Small dish or can lid
•Typing paper

Step 1 – Mix Shellac

Mix four ounces of shellac flakes into a pint of denatured alcohol. Allow the mixture to sit overnight and then filter to remove any un-dissolved material.

Step 2 – Apply Spit Coat

This is the primary coat that is applied three times using a soft cloth – not a brush. Be careful to not over apply to the inlaid work or purflings on the instrument using a cloth application. Use a soft camel hair brush on inlaid work. Let the instrument set for several hours.

Step 3 – Fill Pores and Grain

Some woods – spruce, cedar and maple do not need “pore filling.” Others do. Sprinkle a little pumice from the salt shaker onto a wet cloth soaked with alcohol and olive oil. Gently rub the cloth across the wood surface in a circular motion. Grain fill only small sections of the instrument, always moving grains of pumice with a little more alcohol. Use a damp cloth to evenly remove any stray pumice grains before proceeding.

Step 4 – Additional Coatings

Using a soft application cloth, dip into the shellac mixture and rub along the wood grain applying alcohol as needed to thin the mixture. Never stop moving but employ a circular motion that takes you off the instrument and then back on. Use circular and figure eight motions in a continuous move followed by long pulling strokes. It is important not to keep the application cloth stationary ever for you will be adding to much shellac at the point where you have stopped. Apply at least four additional coatings.

Step 5 – Adjust Mixture

After the initial “spit coat,” you should be applying well-thinned layers of shellac mixed with additional alcohol. Constantly wring the cloth out some to make sure it doesn’t leave a blotting application. Use a piece of typing paper to blot the cloth a bit if you put too much mixture on it.  

Step 6 - Don’t Neglect the Edges

Make sure to properly cover all of the instrument’s edges. Treat these as a separate surface area applying shellac during a different session.

Step 7 – Leveling Process

Using either a rubber block or a cork bottom wooden block, wrap it with 400 grit wet and dry sandpaper paper to “level” the instrument back and top. Use the palm of your hand to sand an instrument neck and sides with a folded 5 X 5 inch piece of 400 grit wet and dry sandpaper. Use olive oil for you sanding lubricant.  Always apply a circular sanding motion and wipe away each area worked frequently to check your finish.