The Technique of FURNITURE MAKING

Wood finishing

The craft of staining, matching, hand and spray finishing is highly specialized and forms a separate trade; the following notes are therefore for general guidance only, and the reader is referred to the standard textbooks on the subject.

GENERAL NOTE

Furniture in general use must be polished to seal the pores of the wood, protect the surfaces, accentuate and enhance the beauty of the figure, create highlights and provide as much resistance against heat or spilt liquids as possible. Earliest polishing materials dating back to the time of the Pharaohs were probably nut, poppy and linseed oils, gums, resins, etc., and it was not until 1820 that the familiar french polish was introduced into England from France. Prior to that Evelyn's Diary refers to the practice of 'Joyners' laying walnut boards in an oven or warm stable, and when the furniture was completed polishing it over 'with its own oyl, very hot, which makes it look sleek and black', while Sheraton advocated using a mixture of soft wax and turpentine. (Furniture was originally made by carpenters and later by joiners who were given exclusive entitlement in 1632 to 'make all kinds of furniture, mortice, tenoned, dowelled and pinned, glued but not nailed together . . .'. Later specialization

produced the cabinet-maker exclusively concerned with furniture). Favourite materials for cabinet-makers of that period were linseed oil for furniture, stained with alkanet root (which yields a permanent red dye) and mixed with brick-dust to produce a polishing putty under the polishing cloth; and hard wax (beeswax, turpentine, copal varnish and yellow ochre) for chairs. Modern practice uses a plethora of materials, natural and synthetic, whose aim it is to hasten, cheapen and give added protection, all of which is achieved to a very marked degree.

It is very doubtful, however, whether any

modern method can match the old processes for sheer beauty, for the secret lay in the patient hand-rubbing over long periods whereby the polish was forced into the pores of the wood, and not applied merely as a surface coating.

POLISHING MATERIALS AND PROCESSES Wax polish

This is one of the oldest and probably the most beautiful of all finishes, as the softened wax penetrates the wood surface and enhances the figure, giving it great depth and warmth. A semi-matt surface with distinctive patina is cheaply and easily achieved, but several applications are required over a period of time for good results. Pure waxes have good moisture resistance but are very easily marked, with little or no heat resistance dependent on the particular melting-point of the wax. Commercial polishes with or without silicone additives for greater protection are usually composed of soft waxes (paraffin, etc.) and are not suitable for first coats on bare wood, although excellent as revivers in finished work. The best mixture for first coats is the old tried formula of pure beeswax and turpentine ( 1 lb [0.450 kg] wax to 1/2 pint [280 ml] turps) dissolved in a water-jacketed pot, and thinned with additional turpentine as necessary. A teaspoonful of pure copal varnish can be added for increased toughness and wear, also carnauba wax (Brazilian palm wax) for hardness and shine. Application should be made with a fairly sloppy paste, rubbed in and stroked off along the grain as in painting with No. 0000 steel wool, and then set aside to harden before burnishing with soft dry cloths. Matt waxes suitable for finishing over thin base coats of cellulose or synthetic lacquer, etc. are composed of soft paraffin-wax and synthetic micro-wax, and do not buff to a gloss finish. A
fairly recent development is teak paste reinforced with ethyl cellulose for increased resistance. One of the chief virtues of all wax finishes is their easy renewal.

Oil polish

Linseed oil alone will give moderate heat and water resistance with high gloss if applied sparingly over a period of several months. Each separate application must harden by oxidization, and 5 per cent white spirits and 5 per cent terebene can be added for easier working, but at least 12 coats will be necessary. This method was often used for dining-table tops but it is much too slow for modern requirements, and sophisticated penetrating oils, teak oil etc., have been developed, incorporating rapid oxidizing agents capable of achieving a sufficient build-up in two coats only. These new oils are used extensively in modern teak and afrormosia furniture, but the resultant finish hardly compares with the older process. As with wax, oil finishes are easily renewed, which is one of the chief advantages.