Screen doors to be effective, must be provided with a spring to close them quickly when open. This spring may be either in the hinge or separate from it. Where a screen door will be in almost constant use, it is probably best to use a good quality of single action spring hinge (with a strong and elastic spring coil), with a simple pull handle for opening the door and a hook or bolt for securing from the inside. A great many special spring hinges are made for screen doors, most of which have the spring coil exposed, as in Fig. 413. Most of these hinges are made of cast iron, although a few are made of solid bronze or cast brass with brass springs; the latter makes a very serviceable hinge, although for the best residences, stores and offices the "Bommer," "Oxford" or "Gem" hinges in bronze or brass, are to be preferred. When exposed to the weather, steel hinges are apt to rust.

Fig. 412   Transom Liffter.

Fig. 412 - Transom Liffter.

Fig. 413.   Columbia Spring Hinge.

Fig. 413. - Columbia Spring Hinge.

Many of the cheap spring hinges for screen doors are made so that when the door is revolved about 135 degrees the spring holds the door open instead of closing it. Such hinges are termed " holdback," and while they are sometimes serviceable, they are not usually as good a hinge for closing the door as the type shown in Fig. 413.

On residences it is often more convenient to use a pair of plain butts, either 3X3-inch, or 3x3-inch, with the spring separate. The spring can then be detached, or the tension released at will.

For separate springs the "Torrey," Fig. 414, is very extensively used, and works very satisfactorily. The tension is adjusted or released by means of the cogs and catch at the top, a small wrench being furnished with the spring for turning the rod.

The "Perfect" door spring, Fig. 415, which is a strong steel spring coil about 17 inches long with a hook at each end, also makes a very good spring for screen doors, as it works nicely and can be very quickly detached. It is secured to the inside of the door at the top, and to the underside of top jamb near the side, by means of screw-eyes. For the screen doors of residences a catch with stop work and a knob on outside and lever handle on inside, makes the most suitable trimming. Such catches are made especially for screen doors, as a reverse bevel is always required. One of the best catches that the author has seen, is the "Willer," Fig. 416, and a very similar flush catch used by the E. T. Burrowes Co., on their screen doors. The screen door catches usually found in hardware stores are very cheap affairs.