Inlaying and Overlaying

What is known as solid inlaying is the easiest form of inlaying for the amateur to adopt.

In this case the inlaid ornamental work goes right through the background. A treadle-driven saw is almost essential, as this has a table which can be tilted to any angle.

Wood J, j%, or ½ inch thick may be used for the purpose. The stuff from which the inlay will be cut, and the background into which the inlay will be fitted, are nailed together and cut at the same time. Now, even the finest saw removes some wood, so if it were kept vertical the inlay would be a loose fit in the background. The difficulty is got over by tilting the table to the left and feeding the work up to the saw while turning it clockwise.

If the tilt be correct, the bevel will cause the inlay to fit the opening in the background exactly when it is put in place . If the work were turned anti-clockwise and the cutting done on the left instead of the right margin of the inlay, the latter would taper in the wrong direction and be too small for the opening.

The worker has to consider tilt and direction carefully to avoid making mistakes. He must also bear in mind that for a given thickness of saw, the tilt should be less for thick than for thin stuff; and that, again, the thicker the saw, the greater the tilt must be.

An inlay is held in place by glue smeared on the edges before it is put in place.

The finest saws should be used for ordinary work, and the starting holes be made with a very fine drill on the lines of the design, since there is liere no waste at any one point in place in both thicknesses. For the same reason the saw must never leave the line when turning.

In what is called relief inlaying, the inlay is rather thicker than the background, so that it projects a little beyond one face. The effect given is then that of inlaying on one side and of overlaying on the other.

Overlaying

This term implies laying a part that has been fretted with the saw KEYS over a solid background, to which it is firmly attached. Overlaying thus gives ornamentation in relief. The background by its rigidity protects the fret, however delicate, from damage, while throwing it up by contrast in colour. (b)

Overlays are cut out of wood veneers fo inch thick; xylonite; aluminium, brass, copper or other metals; tortoiseshell or mother-of-pearl. By using the various materials in conjunction, very handsome effects can be obtained.

Wood veneer is too fragile to be cut as a single thickness. So either two or more overlays are cut simultaneously out of as many thicknesses fixed together – the design or designs being on the top one – or the veneer is supported by a piece of waste wood. If a sheet of paper is pasted to the back of a veneer before cutting, any part that may break away will be held in place for attachment to the background.

Metals are sandwiched between two thin boards for cutting with a No. 1 saw. Hand-cutting is better than treadle-cutting in this case, as the saw must be used slowly. A thickness of about inch is recommended. Where aluminium is used it should have been prepared for the purpose, with one satin surface. Brass and copper will need polishing and lacquering, and whatever the metal be, its edges will require the removal of any burr left by the saw. Metal overlays are attached to the background by liquid glue, and by round-headed screws or pins of suitable colour.

Xylonite, imitating ivory, tortoiseshell, mother-of-pearl, etc., should not be thinner than -h- inch, and have one side unpolished, to enable the glue used for fixing it to get a good hold. This material outs easily. It should be supported by a board of waste wood, while being fretted, or be sandwiched between two boards.

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