How to Apply and Repair French Polish
The simplest way of applying French polish is to buy a proprietary DIY material, but it may still be bought in a number of forms in specialist paint shops under the name of garnet polish, button polish, white polish or transparent polish. All are based on shellac, carrying only in color. And all are applied in a similar manner.
Applying French polish
Careful preparation is vital. Timber must be clean, dry and well smoothed with fine glass-paper, then the dust removed, ideally with a tacky rag – a special duster impregnated with a resin which is tacky enough to pick up fine wood dust, but not too sticky.
Choose the shade of polish you require, keeping in mind that the darker polishes darken the wood considerably. Experiment with both the technique and the color first on a scrap piece of wood. If a more drastic color change is required, stain and smooth the wood before polishing.
The secret of successful French polishing is to apply it on a polishing rubber, which you can make using a lint-free cloth, such as an old, clean white handkerchief and a wad of clean cotton wool. Make sure the cloth has not wrinkles. Polish should ooze slightly through the cloth, but avoid over-soaking.
Work the polishing rubber evenly over the whole surface to be polished in a continuous figure of eight movement. Continue until the surface has as even layer of polish, then after a few minutes repeat the process several times to build up a series of thin layers. Make sure that edges and corners get their share of the polish.
The next stage is called spiriting off. Leave the surface for at least eight hours then make a new rubber with a double layer of cloth, and soak the cotton wool in methylated spirit. Squeeze the pas until almost dry. Too much spirit would merely dissolve the polish.
The aim of spiriting off is to remove any marks left by the rubber and to give a sparkling finish. Use a figure of eight motion applying increasing pressure as the rubber dries out, use fresh cloth from time to time, and then finally work in the direction of the wood grain, continuing until the surface is perfect. Although the polish dries fairly quickly, it takes several days to harden completely.
Repairs to French polish
You can establish whether a surface has been French polished by applying a lint-free cloth dipped in methylated spirit to the surface. A light rub will immediately soften a French polished surface and there will be deposit on the cloth. Other finishes, such as polyurethane, will be unaffected by methylated spirit.
Scuff marks – Prepare a solution of 5 parts methylated spirit, 2 parts raw linseed oil and 1 part pure turpentine. Make up a soft cloth pad and use a figure of eight motion to work the mixture over the damaged area. If there are deeper scratches, use neat methylated spirit to soften the existing polish so that it can be blended together over the scratch marks.
Bad damage – Strip off the existing finish with neat ammonia, acetone or varnish remover. Then proceed as for new French polishing.
Heat marks – Rub the affected area with a mixture of 1 part pure turpentine and 1 part raw linseed oil or camphorated oil.
Spilt alcohol – This acts as a solvent to French polish. Wipe off spills as soon as possible and leave the surface to dry. If polish has been removed by the alcohol, treat the area with French polish substitute, obtainable from many hardware stores. Apply it with a small brush until the surface has been built up. Leave to dry hard, smooth with flour-grade abrasive paper, then use the rubber, as for scuff marks.
Scratches – Special scratch repair sticks are available from many DIY shops, supplied in a number of wood colors. Rub the appropriate color stick into the scratch, and then blend it by rubbing over lightly with a soft cloth.
Cigarette burn – Gently remove the damaged polish with a razor blade tip. If the damage is shallow, use a scratch repair stick. If deep, drip in some melted colored beeswax, available from paint store. You may need vegetable dye to color the beeswax to match the existing finish.
Water stains – White marks can often be polished out by rubbing the area with metal polish wadding. Rub vigorously to generate heat. Black marks may not respond, in which case the existing polish will have to be removed and new polish applied.
WARNINGIf you have valuable antiques in need of restoration, do not try to polish them yourself. Get them treated by a reputable furniture restorer. This way you will be assured of retaining the full value of the piece.
