=13. Cast-Iron Weights.=—The term =sash weight= is applied to a
counterweight used for balancing double-hung, or sliding, sash. These
weights are generally very rough, being made from either the poorest
iron or waste iron. The stock sizes are usually long and cylindrical
in form—from 1⅜ to 2¼ inches in diameter—have an eye cast in the upper
end, as shown in Fig. 10, and weigh from 2 to 30 pounds, the weight
determining the length of the sash weight. In Table V are given the
weight, diameter, and length of sash weights as they are generally
furnished to the trade, although it is almost impossible to give this
data with any degree of accuracy, as the different manufacturers vary
the diameters of the weights slightly, and this changes the length
measurement. Square weights or special weights can be easily procured
at small additional cost.
[Illustration: FIG. 10]
[Illustration: FIG. 11]
=14. Lead Weights.=—The weight of lead is about 80 per cent. greater
than that of cast-iron; hence, =lead sash weights= must be resorted to
where the construction of the pockets is too narrow to permit the use
of iron weights, or where heavy plate glass is used. They are also used
in cases where the sash are very wide and low, as here a short weight
must be used in order to obtain the necessary travel for the sash.
Lead weights can be procured in either round or square shapes, and of
any diameter or measurement to suit existing conditions, but they are
generally made to special order. A wrought- or malleable-iron eye, or
fastening, for applying the cord or chain is usually inserted at the
top. The cost of lead weights, however, is generally five times as
great as that of iron weights.
=15. Sectional Sash Weights.=—There is a form of sash weight in the
market known as the =Walda sectional weight=, which is illustrated
in Fig. 11. This weight, as will be observed, is so arranged that
units or sections may be detached or added, as desired, to diminish
or to increase the weight. Such a weight can be nicely adjusted to
counterbalance any sash, and has the advantage over the cast-iron
weight in that each part is interchangeable and no mistake can be made
in ordering, as the necessary weight for any sash can be made up on the
site.