There are two basic subgroups of two-dimensional scenery: hard scenery and soft scenery. Hard scenery usually refers to flats, and soft scenery usually refers to unframed units like drops and draperies.
Flats are lightweight frames made of wood or steel tubing. They are usually covered with muslin but when necessary are covered with such materials as plywood, Upson board, paper, Masonite, velour, or other material. There are three general types of flats. These are soft flats, studio flats, and metal-framed flats. There are also door and window flats.
Drops and draperies as well as other unframed fabric units are what are referred to as soft scenery. These are usually suspended from the grid, a batten, or some other type of structure capable of supporting their weight. Drops are flat and large curtains that have no fullness.
There are two types of draperies used in the theatre. One of these are stage draperies and the other is drapes and curtains.
Flats are always lightweight frames. They are sometimes made of wood and other times made of steel tubing. The type of covering depends on what it is going to be used for. The various pieces that make up the framework of a flat have specific names. Rails are the name for the top and bottom horizontal parts. Stiles are the outside vertical pieces. The interior horizontal pieces are called toggle bars. On the upper and lower corners of the same side of a flat over three feet wide are corner braces.
One major type of flat is a soft flat. This is usually a wooden-framed flat covered with some type of fabric. Most soft flats resemble tall rectangles from one to six feet wide and eight to sixteen feet high but they can be designed to be almost any shape and size. The wooden framework for a flat up to fourteen feet tall is usually made of 1 X 3 white pine. This wood needs to be light in weight, straight grained, fairly fee of knots, and most importantly, straight.
Flats that are more than 14 feet tall usually need the additional strength offered by 5/4 by 4 stock. Outsized flats are often built from 18-guage, one-inch-square steel tubing because five-quarter stock is comparatively expensive. The face of the steel frame is covered with ¼ or 1/8 inch plywood that is attached with power-driven, self-tapping screws, and the hard surface is covered with appropriate cloth material.
To keep the stiles parallel toggle bars are used. When the flat is painted fabric shrinkage would cause the stiles to twist and bow in toward each other if toggle bars were not used. Toggles should be spaced about four to five feet from the nearest toggle bar or rail.
Another common type of flat are studio flats, which are often called Hollywood-style flats. These are framed flats that are covered with a hard material like plywood. They are made using the same general framing layout as a soft flat except that the framing wood is placed on edge rather than flat. This is for strength.
The process of constructing a flat from square metal tubing instead of using 1 X 3 lumber is almost identical. Instead of lumber eighteen-gauge, 1 inch X 1 inch square tubing is used. All the joints are welded. Keystones and cornerblocks are not needed in this type of flat, unlike most wooden framed flats.
The other major type of soft scenery, drops has several subtypes as well. Tie-supported drops is one of these subtypes. Most likely the easiest way of hanging a drop is to tie it to the batten. Ties can be made from strips of scrap muslin, heavy cotton tape, very long shoe laces, and other materials. Ties are attached to the top of the drop then tied to the batten.
Another subtype is batten-clamp drops. Drops are sometimes attached to a counterweight batten with batten clamps. Rapid hanging or removal of a drop from a batten is helped by batten clamps. The top of the drop is sandwiched between two 1 X 3s. The batten clamp is designed to hold the wooden batten “sandwich” without touching the drop.
Opaque drops are usually made of heavyweight muslin and painted with opaque paints and lit from the front. The audience cannot see through them.
Translucent drops are also made of heavyweight muslin. They are painted with dyes or a combination of dye and opaque paint. They are then lit from both the front and back. This makes the areas that have been dyed translucent which increases the apparent depth of the scene.
Scrim drops are made from sharstooth scrim or theatrical gauze. They have the unique ability to become transparent when the scene behind the drop is lit. They can be painted with dyes or thinned paint.
Cutout drops have pieces or sections of the drop actually cut out of the material. The use of a series of cutout drops placed in front of one another can greatly enhance the sense of depth in a design. These kind of drops are painted before they are cut to keep the edges from curling.
Source:
Limited experience in a scene shop
Gillette, J. Michael. Theatrical Design and Production. 4th ed. Mountain View: Mayfield, 1999