Application Information
• Shellac Polish Application • Shellac Sanding Sealer Application • Aquastain Application • Aquacoat SP Application • Aquacoat XTRA Application • Polyurethane Varnish Application • Transeal Application

• What is Shellac?
• Making a Polishing Rubber
• Using the Polishing Rubber
• Spiriting Process
• Brushing French Polish

What Is Shellac?

Lac is a natural substance that is the secretion of the Lac insect "Laccifer lacca", which is found on certain tress principally in the provinces of India and Thailand. The lac insect, in the larval stage, is about 0.5mm in length and sufficiently mobile to crawl along the branches of the trees to find fresh succulent twigs. When it has fixed its position it secretes a protective coating consisting of a deep-red scale and a yellow to reddish resin called Lac. Its life cycle is about 6 months with most of the resin being secreted by the female insects. The substance is collected from the trees, cleaned and harvested into bags. The bags of harvested lac are heated over an open fire and as the lac melts, the bags are squeezed so that the lac is forced to the outside surface of the bag. This process forms sheets of shellac which are then crushed into flakes for storage and despatch.

Shellac - click for larger image

The dissolving of shellac flakes in alcohol is the most widely known use of shellac and forms the basis of French Polish. No resin has yet been found which so enhances the natural beauty of the grain of wood.

The technique of applying shellac by rubbing it onto the furniture with a "rubber" is widely regarded to have begun in France in the early 1800's, hence the description French Polish.

Shellac is not only used to produce French polish, it has had a distinguished history of coating many different products.

Gramophone Records Paper Coating (e.g. playing cards) Electrical and Insulation
Hats (stiffening agent) Leather Dressings Adhesives
Confectionery Glaze Pills Glaze Dental Compositions

Making a Polishing Rubber

Products required:

• Polishing Cotton 100% (lint free)
• Cotton Wadding or Cotton Wool
• French Polish (any type)
• Linseed Oil or Mineral Oil (optional)

Process:

1. Tear off a 6-9 inch square of cotton wadding and fold it in half, fold the corners of the rectangle to form a triangle
2. Fold the outer corners of the triangle to make a pointed pad with a smooth sole
3. Cut out a 9-12 square inch piece of Polishing Cotton and diagonally place the pad of wadding across the centre of the cotton square
4. Proceed by wrapping, in turn, all the triangular corners of the cloth over the centre
5. Gripping the wrapped pad in one hand, twist the loose fabric together to make a firm rubber
6. Fold the twisted ends of the cloth over the pad to fashion a handgrip, leaving a smooth, crease-free sole.

The polish is applied by opening the pad and charging the cotton wadding with approximately 4 tablespoons of polish. Ensure that you avoid dipping the rubber directly into the polish and do not pour it onto the sole of the pad. Close the rubber and squeeze out any surplus. Putting pressure onto the rubber allows the polish to seep through onto the surface. Raw linseed oil can be smeared onto the sole of the pad so that the rubber runs smoothly.

The rubber should be recharged when necessary and the entire process repeated until the grain is filled. This is what is termed as 'bodying up'.

Using the Polishing Rubber

1. Begin by sweeping the rubber smoothly on and off the surface using parallel strokes
2. After a few applications using the parallel method, coat the surface by alternating circles and figures of eight. This combination of different strokes will distribute the French polish evenly
3. To rub out any blemishes leave the polish to dry overnight then lightly sand out any dust particles that have become embedded in the surface. Using very fine sandpaper rub along the grain and wipe of the dust with a clean duster
4. Ensure that you work to the edges of the panel and don't stop moving the rubber or you will leave a mark
5. This sequence should be repeated until a satisfactory build has been achieved, depending on the substrate this can be in excess of 20 coats
6. After the final application, let the piece dry for several days before proceeding with the spiriting process

Spiriting Process

In most cases this will be the final stage, which is designed to burnish the polish to a high gloss. Use thinned down polish to a ratio of three parts 2½lb polish to 1 part Methylated Spirit.

Charge the rubber with the thinned polish and using very light pressure, apply the polish in straight very slightly overlapping strokes along the length of the grain.

The stroke must be very straight or you will produce an arcing pattern to the finish. When all the pieces have been treated in this way, wait a few minutes and then repeat the sequence. This time you should feel a very definite pull as the surface film is partially dissolved and pulled flat by the rubber. The resistance to the rubber's movement may tempt you to speed up; this must be avoided as the surface will be 'burned'. For the best results slowly pull the rubber over the surface. If you have any problems wait for a time before starting again.

Stop when you have achieved a high, even gloss. There may be some blemishes, such as minor rubber marks. These will normally disappear as the surface hardens. If not, repeat the spiriting process after a few hours.

Brushing French Polish

French Polish can also be brushed onto the surface and it is recommended that a good quality polishing mop is used (either an S&R squirrel or zorino).

1. Load the mop with French polish and apply to the surface, wait for about 20 minutes, then rub down with S&R sandpaper
2. Repeat the process twice more
3. Rubbing with S&R OOOO steelwool apply SUPERWAX polish to the now hardened polish. Rub fairly gently along the grain, making sure you cover the whole surface evenly
4. Finish with a soft S&R duster by rubbing the polish to a shine