Window Glass Putty

New sash must receive a priming coat; if the sash is to be painted, this is a priming coat of white lead containing perhaps four or five pounds of white lead to the gallon; but if the sash are to be varnished, they are primed with oil alone. The oil usually has a little drier added to it, or boiled oil is used;, but, as has been explained, boiled oil is not much used for priming coats. The special object of priming is to prevent the wood absorbing oil from the putty.

Ordinary putty is a mixture of whiting (pulverized chalk) and raw linseed oil; some makers add about five per cent cotton oil, to increase the keeping quality; it is mixed to a stiff mass, like dough, by machinery; but, like dough, it can be equally well made by hand. Machine-made putty of the best quality can be made and sold by the ton for three cents a pound; but it is almost impossible to buy good putty in the open market; marble dust is substituted for whiting, and rosin and mineral oil for the oil, and this putty is an injury to the consumer; it will not hold the glass in, it crumbles and falls out, and then the glass falls out and breaks, or if it is not allowed to go so far as that, it becomes necessary to take out the window, clean off the old putty and replace it.

The conditions have become so bad that good retail dealers have their putty made by hand by their own employees. At three cents a pound, a dollar will buy enough to putty all the glass in an ordinary dwelling-house. The man who is having a house built will do well to provide in his contract that he may retain from the contract price the sum of one dollar per window for two years, to be forfeited if the putty crumbles in that time. Then the builder will be interested in the matter; he can probably save only half a dollar on the whole house by buying inferior putty; and if this were generally practiced, this nuisance of adulterated putty would shortly disappear. Good putty lasts a lifetime.

White lead putty is too hard for setting window glass; the glass may be broken, and then the putty must be removed, and it is very difficult to do this with white leaded putty; but one-tenth white lead may be put in ordinary putty with advantage, as it makes it quicker to dry. Putty is applied with a putty-knife, which has a steel blade about 3½ inches long and 1¼ inches wide at the end; some use a blade cut square across, others have the end beveled; it is purely a matter of habit; either will do the work.

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