A Manual of Mending and Repairing; With Diagrams

by Charles Godfrey Leland

“Among the thousand mad schemes which were proposed by projectors was one for making sawdust into boards.”—History of the South Sea Bubble.

Very few people, even among workmen and artists, are aware of what remarkable and curious restoration the most decayed pieces of wood are capable. We will, however, begin with the simplest repairing, or that of furniture.

When articles of furniture have been strongly and properly made of oak or other hard wood, and as properly used, they will last for centuries; and should some unforeseen accident take away legs or arms, they can be perfectly replaced, especially in the admirable old-fashioned German objects of the kind, which were all put together with wooden pins or by means of mortise and tenon, so that, when need required, they could be packed as boards;—nor were they the less elegant for this. But if furniture be simply sawed from soft, cheap deal or poplar, and merely glued together (as most cheap furniture made in England is), it will soon warp and break up, and all the mending in the world will not make it better than it was when new. Glue is, therefore, the great material for most woodwork, and, as I shall show, in two very different forms.

Having a broken chair-leg, which can, however, be fitted together, first prepare your glue in a proper kettle—that is, a balneum mariæ, or one kettle in another. In the outer is only boiling water; in the inner the glue, mixed with water. The reason for this is, that glue, when softened with water, dries up very rapidly under the action of air or fire, while the softer heat of water keeps it, so to speak, “alive.”

But if, while the glue is soft, we pour, say, a teaspoonful of nitric acid into half-a-pint of glue, it will remain soft a much longer time—which is a valuable secret to many, especially where large, broad surfaces of veneers are to be glued on, and where, the process being slow, it is desirable for the adhesive to remain soft for many minutes. And here I would mention that the acid-glue will remain in a liquid state for one year if tightly corked up in a bottle. Its only defect is a disagreeable, pungent smell.

This glue can be improved by being made as follows:—Take of best glue three parts, place them in eight parts of water, and allow the mixture to soak some hours. Take half a part of hydrochloric or muriatic acid and three-quarters of a part of sulphate of zinc; add to these the glue, and keep the whole at a moderately high temperature till fluid—that is to say, boil the glue as usual in a balneum mariæ or in hot water, after soaking it all night in water. Then stir in the hydrochloric (or muriatic) acid and sulphate of zinc. This is a first-class glue. Keep it in a bottle with an oiled cork; any other stopper would adhere. But for all ordinary work the glue, with nitric acid, will suffice, as it holds with great tenacity to anything.

This glue, which keeps liquid for a long time, and which holds without scaling off, as common glue often does, may also be made with very strong vinegar. The latter, in fact, amounts to the same thing in most European countries, but especially in the United States, where, according to the New York Tribune, there is literally no vinegar sold or made, save from sulphuric acid and water. Perhaps when mankind shall have reached a higher stage of civilisation, all dealers will be compelled by law to place on every article of food sold the list of ingredients of which it is composed. We should then know how much oleomargarine passes for butter, and what proportion of “delicious conserves” are manufactured from apples alone or turnips.

Observe that in glueing ordinary wood together the two pieces to be attached should be gradually but very well heated first. This renders them more inclined to “take” the glue. This is applicable to other substances.

Also note that when two surfaces have been made to adhere with ordinary water-glue, should they come apart when cold, it is very difficult to make them unite again. But this is not the case with acid-glue. And if you have such surfaces which will not unite, wash them with nitric acid or very strong vinegar, and the glue then applied will “take.” Also observe that the acid-glue is far stronger than the common kind.

Having the broken leg fitted, first with a narrow gimlet or brad-awl make a hole crossing the fracture, then glue the pieces together, and before the glue dries put a screw or two through the hole; i.e., screw the pieces together. This will hold perfectly, if you will sink the head of the screw in the wood, smooth it with a file, then putty it over and paint it.