Stains and Finishes for Radio Cabinets

Radio Record, Volume III, Issue 22, 13 December 1929, Page 30

Stains and Finishes for Radio Cabinets

Practical Notes from a Practical. Writer

Contributed by

G.

H.

Otahuhu).

IT building radio cabinets suitable for a fine finish, the grain should be well laid. This is done before the work is put together, by rapidly. wetting the surface of the dressed timber. On drying, it will be observed that the surface has rougliened, due’ to the raising of the grain. It is then smoothed down again by means of the scraper and: No. 00 sandpaper. No. 1 sandpaper, finishing with No. 00, will do if the amateur cannot use the scraper properly. This operation may be repeated with advantage ‘ $Stains. (a) Raw linseed oil, together with @ little drying oil, such as Japan oil or Terebine. (b) Bichromate of Potash (not permanganate), about 1 to 2o0z. dissolved in a pint of boiling- water. This stain burns the surface, and produces a darker and more "mellow" effect than "oiled" Rimu. . (c) Browns: Vandyke Crystals. About 20z. to 1 pint of water. This is brought to the boil and allowed -to Simmer for 15 to 80 minutes. Stir well or will rise in a similar manner as milk. This stain produces a beautiful rich brown. (d) Japan black, diluted with genuine turpentine. This is a colder shade than "C." {e) Black: Nigrosine dissolved in methylated spirits. One ounce may be purchased, and is sufficient for most needs, (f) Rosewood: Naylor’s Rosewood Crystals, dissolved in methylated spirits. One ounce may be purchased, and will probably be sufiicient. This is a sbeautiful rich rosewood, and unless the colour clashes with its environments, the writer considers this the best for wireless cabinets. All these stains may be obtained from any oil and colourman, with the exception of F. This may be obtained from Messrs. Guthrie Bowron, Auckland and Wellington. ’ The quantities in the above directions aré only approximate; the desired intensity is obtained by testing on the back of the woodwork. ‘HH stains should be applied with a brush and lightly wiped over with a rag.. This removes superflous pigment and brush marks, and exposes’ the grain of the timber. The colour of the wet stain (with the exception of B) will give a good indication of the finished colour. If too light at this stage, apply another coat; if too deep. wipe with a rag moistened with the solvent (water or spirits, as the case might be). When quite dry, apply two coats of knotting (3 or 4oz. shellac. dissolved in methylated spirits). These two coats must be very thin, in order to "flow" evenly. Lightly sandpaper’

between and after them, and the work is then ready for the "finish." RENCH polish is, undoubtedly the king of "finishes," but. as this is only" successful in the hands of an expert, I omit it in favour of methods applicable to the. ordinary handy-man. The secret of good varnishing is absolute cleanliness in the matter of pot, brush and varnish, keeping the work dustproof until dry, and the use of plenty of No. 00 sandpaper between the coats (always rubbing with the grain of each piece of timber). For a-rich high gloss, which will be better than French polish poorly done, apply three coats of the best "pale carriage varnish" at intervals of not less than four days, rubbing down between each coat until eyery trace of gloss disappears. For a dull finish, use eggshell varnish, as above, sandpapering lightly between coats. Should this finish be too dull for the worker’s taste, any degree of brilliancy may be imparted by adding arriage varnish to the’ eggshell varnish, and some beautiful soft. polish effects may be obtained by this method. In New Zealand, our cabinets are usually made of rimu, kguri, or oak, and their most suitable stains are: Rimu-Any of the above. Kauri-For C, D, © and F, and is the best timber for E and F. Oak-aA, C, D and E. Generally speaking, oak should be finished in eggshell varnish with very little carriage varnish. ANY attempts have been made to obviate the sombreness usually associated with wireless panels The metal panels in shielded sets demand some treatment, and here is an opportunity to tread new paths with profit. The following colours were used with delightful effects on the panel of a rosewood polished .console with black dials. First of all, the panel was painted a very. pale green and "granited" with green, brown and white. To do this, the colours are mixed up thinly with turps and a little terebine. A little of the green (a deeper shade than the panel) is poured on a board.or palette, a small cheap sponge with a flattened surface is worked in the Colour and then lightly but firmly daubed all over the panel, turning the sponge round a little each succeeding daub to avoid a marked "pattern." The sponge is cleaned out with turps or kerosene, and when the work is dry or nearly so, the process is repeated with the brown, and then with the white. None of the colours should be too prominent. If they should be so, "soften out’ by lightly daubing over with the colour or colours necessary (the ground colour may help). The colours should be. thin enough to be semi-transparent ‘when daubed on the panel."