French Polishing is a finishing technique process for wood that leaves a very high gloss surface with a deep colour and reflective properties. It became prominent in the Victorian era and was commonly used on mahogany and other expensive timbers. It involves applying numerous thin layers of shellac melted in denatured alcohol, best applied using a rubbing pad lubricated with one of a variety of oils. This is normally made of absorbent cotton or wool cloth wadding inside of a piece of soft cotton cloth. The final finish is recognised as the most stunning way to finish highly figured wood. It is less forgiving than modern Lacquers and Varnishes and can be easily marked. It is susceptible to water, alcohol and heat damage. However, it is also easier to restore than a damaged varnish finish, as patches can be easily blended into an existing finish.
Types of French Polish
French Polishes are made up from flaked shellac dissolved in methylated spirit. The type of shellac used can vary in colour from a light clear colour to a dark brown colour.
- Special Pale French Polish is a de-waxed Shellac and is suitable for use on both light and dark woods. It will enhance the natural colours of the timber.
- Button Polish is light brown in colour and is ideal for use on light woods such as elm and light mahogany.
- Garnet Polish is deep brown in colour and is mainly for use on darker timbers such as walnut and dark mahogany.
- White Polish has a milky appearance and can be used on light timbers such as ash and natural light oak.
- Black Polish is a jet black polish and is used in the ebonising process.
French Polishing requires patience and practice. It should first be tried out on a spare piece of flat wood, with the polishing area in a warm, dust free environment. There are many methods of French polishing and every French polisher has his or her own method which is developed over time. The method described in this leaflet will give you the basic skills to further advance in your own time.
Making French Polish
Once you have mastered the art of French polishing you may wish to make up your own French polish. This will allow you to adjust the strength according to your own personal preference and produce your own unique finishes. To do this you will need shellac flakes of the colour of your choice, methylated spirit and a glass jar.
Tip the shellac flakes into a jar and cover with methylated spirit. Replace the lid and shake the mixture then leave it for 24 hours, shaking occasionally until the flakes have fully dissolved. A typical receipe for French polish is mixed at a ratio of 250g shellac flakes to 1L methylated spirit. If a thicker polish is required this can be increased to 500g shellac flakes to 1L methylated spirit. Once the French polish has been made it will have a shelf life of approximately six months, after which it may start to deteriorate. We therefore recommend that you only make up sufficient polish to complete the job in hand.
Type of Shellac Flakes
Blonde De-waxed Shellac Flakes produce a light transparent coloured French polish. Used for antique restoration and on light coloured woods.
Lemon Shellac Flakes produce a pale gold colour and can be used for furniture restoration and light to medium coloured woods.
Button Shellac Flakes will produce a golden brown polish that is suitable for restoration work and darker timbers.
Garnet Flakes produce a dark brown French polish ideal for dark woods and restoration work.
Preparation & Materials
Preparation of the surface to be polished is extremely important and to achieve the best results it is necessary to remove any slight imperfections which may not be noticeable under a varnish or wax finish. This may involve stripping off an old varnish with Liberon Fine Wood Stripper or removing a wax or oil with Liberon Wax and Polish Remover. Once stripped you will then need to rub the surface down with fine abrasive paper to obtain a smooth finish. If the wood is open grained and a mirror like finish is required the grain should be filled using a suitable grain filler. Alternatively extra coats of polish may be applied and then cut back between coats with Liberon Ultra Fine Steel Wool (0000) until the grain has been filled.
How to Make a French Polishing Rubber
French Polish is applied using a French polishing rubber. The rubber is made by wrapping a piece of lint free cotton cloth around some cotton wadding or cotton waste. Place a handful of cotton wadding into the centre of the cotton rag, bring in the four corners of the way and then twist to form a pear shaped pad, ensuring that the base of the pad is flat and free from creases or defects as shown. The size of the rubber can vary according to the user or the size of the job to be completed.
How to Apply the Product
Load the rubber by pourding the French polish directly onto the cotton wadding. Do not pour the polish directly onto the face of the rubber. Bring the corners together and twist as before squeezing the polish to the face of the rubber. Any excess should be squeezed out before you commence polishing. If there is too much polish on the rubber this will cause ridges on the work. These ridges will then have to be rubbed down when the polish has dried and the process restarted from the smooth surface.
How Much Polish is Needed?
Too much polish - if lots of polish comes through the rubber when it is pressed onto the surface then too much polish has been applied. Not enough polish - if barely any polish comes through the rubber when it is pressed on to the surface then not enough polish has been applied. The corrent quantity - the rubber should move freely on the surface but not leave lots of polish behind.
Applying the French Polish
The first applications of polish are made by passing the rubber up and down, working along the grain of the wood and slightly overlapping the previous pass. These first few coats will act as a seal, ready for the further coats and are known as fading up. If the rubber feels as if it is dragging squeeze the sides very gently to push more polish onto the face, or ease up on the pressure being applied to the rubber.
Further applications are made by using the rubber in a circular and figure of eight motion. The final pass in the sequence goes with the grain, passing fairly quickly and lightly over the surface. Always finish the sequence along the grain. The rubber should always be slid onto the work from one side and off the other during the polishing stroke. Placing the rubber on the work and then starting the stroke will create a mark, which will be very difficult to remove. Likewise the same problem will arise if the rubber is stationary on the surface, this is because the alcohol will immediately start to reactivate the previous coating. After several applications the rubber may not slide so freely over the surface. To rectify this add a drop of Linseed Oil to the base of the rubber, ideally by dabbing it on with the tip of your finger. This will allow the rubber to move freely once more. Take care not to apply too much oil as this will leave a smearing effect on the surface and will have to be removed at the end.
After every 4 or 5 applications the work should be left to harden for a couple of hours before applying further coats. We recommend lightly rubbing the surface down between coats with 320 grit abrasive paper or Ultra Fine Steel Wool (0000) to remove any blemishes.
Once a sufficient layer has been achieved on the surface spiriting off can commence to produce the final high gloss finish. A new rubber must be charged with French polish that has been thinned down with methylated spirit. Approximate ratio: 2 parts French polish to 1 part methylated spirit. Apply this polish as before in a circular or figure of eight motion and again finish by going along the grain. Finally, pour a small amount of methylated spirit and a small amount of French polish, at approximately a 50/50 split, into the rubber and rub this up and down the work to remove any high spots. Move the rubber lightly and quickly over the surface to achieve a gloss finish.
A French polish finish does not have to be a high gloss mirror finish every time, sometimes a softer level of sheen is required. To achieve this all you have to do is to allow the polished surface to harden for a few days then cut back the polish using Liberon Ultra Fine Steel Wool (0000) to remove any imperfections. Finally finish with a coat of Liberon Black Bison Fine Paste Wax. For a mirror finish you need to leave the French polish to fully harden for about a week to ten days, then cut the surface back with Ultra Fine Steel Wool (0000) and remove any dust with a tack cloth. Next apply Liberon Burnishing Cream with a clean cotton cloth, polishing vigorously and occasionally turning the cloth until the deep mirror finish is achieved.