The Technique of FURNITURE MAKING
MARKING/LAYING OUT
Face-marks and edge-marks must be bold and should be done with a thick soft pencil. For the first approximate dimensioning of lengths, etc. a B or HB pencil can be used, but for accurate dimensions at later stages a 2H or 4H is necessary, while shoulder-lines should always be marked with a knife.
SAWING OUT
The rip-saw is used for long-grain sawing, the large crosscut or crosscut panel-saw for cutting across the grain, and the temptation to use the finer tenon - and dovetail-saws for rough work should be strenuously resisted, for more often than not the plank will be gritty. A usual tendency on the part of the beginner is to saw too fast, and in comparison the skilled worker's pace is almost leisurely, but he will cut more wood in the end and it will be accurate. Every effort should be made to saw not only on the line but also truly vertical, as this will save not only
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129 Cross-cutting plank with handsaw |
material but a great deal of unnecessary work at later stages. At the commencement of the cut the heel of the saw should be placed on the mark, steadied in the vertical position with the thumb and the kerf established with a few light upward strokes, not forgetting to withdraw the thumb out of harm's way before the full downward thrust is applied to the saw (129). A few strokes with a candle end along the saw-blade will reduce friction and lighten the work.
PLANING (SURFACING)
Either the fore - or jack-plane is used for the first rough levelling, the try-plane for true levelling and the finely set smoothing-plane for final surfacing. Contrary to the practice recommended by some writers, the cutting edges of the irons should be square and not ground convex, although the jack-plane iron can have the corners dubbed over to prevent digging in. The set of the back iron should be adjusted to the depth of the cut required and the relative hardness or softness of the wood, for its sole function is to support the cutting iron and break up the chip, and therefore it can be set back as much as 1/16 in (1.5 mm) for mild softwoods, but perhaps only 1/64 (0.5 mm) for hardwoods. The projection of the cutting iron also depends on the nature of the board; it should be fed down gradually until it gives a clean easy shaving without shuddering or digging in. The sole of the plane can be lubricated with the candle end to cut down friction.
In planing wide boards the best or face surface should first be levelled off along, across or diagonally, according to how the grain works (interlocked grain is best planed diagonally to prevent tearing out), and tested with the winding-sticks, placing one at each end and sighting through with the eye level with the nearest stick and about 12 in (305 mm) away. Any slight tilt to the further stick will then disclose whether the board is twisted, for although all edges may appear straight the diagonals may be curved. If the tilt to the further stick is, say, 1/8 in (3 mm) then it can be assumed that the board winds 1/16 in (1.5 mm) in its length, and about half that amount must be taken off the high further corner, and the other half from the near opposite corner by working diagonally across the board. When the board is out of wind then the try-plane should be capable of taking fine shavings the full length of the board over the entire area, to be followed up by the finely set smoothing-plane to ease out any ridges and roughened patches. During all these operations constant watch should be kept on the general levelness along the length and across the width, either with a straight-edge or the sole of the try-plane tilted on its edge. No attempt should be made to scrape or sand the surface at this stage for it is bound to attract small scratches, bruises and dents during subsequent operations, but badly torn grain should be got rid of as much as possible so that little if any thickness will be lost in the final finishing. When the surface is planed perfectly true and out of wind it should be marked with a 'face' mark (12 8B) which should never be omitted from any piece of prepared wood.
