CHAPTER 21
Metal Frame Construction
In recent years, metal framing has become increasingly popular as a medium for scenic
construction. The use of welded steel or aluminum tubing allows scenery to be constructed
from materials that are smaller in cross section, more securely joined, and in some cases lighter
than traditional wood framing. This method has the added advantage of being very quick to
assemble using easily constructed jigs. Furthermore, there is actually more salvageable material
left from steel framing than from the wooden type. Metal framing from tubing is the only
logical approach to constructing some scenic units with open structures and odd angles.
MATERIALS
The phrase metal framing could mean either aluminum or steel. There are advantages and
disadvantages to either product. Aluminum is much lighter than steel, but steel is considerably
stronger than aluminum, which has a tendency to crack and shatter. Welded steel square tube
is much less expensive than its extruded aluminum counterpart. Aluminum is more difficult
to weld than steel is, and requires special inert gas techniques that are more difficult to
produce. Aluminum framing is very popular with companies who build scenery for tours of
rock-and-roll shows because of its light weight, but they have almost unlimited financial
resources. Steel framing is much more popular with schools and smaller theatre companies.
© 2010 Elsevier Inc. All rights reserved.
doi: 10.1016/C2009-0-23409-X
340 Illustrated Theatre Production Guide 2 ed
Square tube gets its name from the shape of the
cross section, which is, of course, square. It is quite often
the most useful shape, although tubing is also manufac-
tured in round or rectangular cross sections. Steel tube
is bent into shape from flat bars of metal, and as a result,
one side of it has a seam where the edges of the bar have
been welded together. This seam generally appears as a
slightly darker, sometimes bluish stripe.
Aluminum is extruded through a die in order to get
whatever particular shape is required. Cutting and
grinding steel framing requires the use of special metal-
working equipment, whereas the much softer alumi-
num can usually be cut and shaped with ordinary
woodworking tools. Welding aluminum requires a TIG
or MIG welder, whereas steel may be worked with an
ordinary arc welder, or even oxyacetylene.
This chapter is written with steel tubing in mind,
because it is more widely used, but there isnt that much
difference in the types of structures you can build with
either one.
Building the structural parts of a set from steel
square tube can actually be less expensive than using
wooden parts. The difference in price is due to the way
steel joints are welded together. The resulting connec-
tions are much stronger than any kind of wooden
joinery, and you can easily make angular shapes that are
much more difficult with wooden scenery. Less bracing
is required, so fewer running feet of material are needed
for steel structures than for traditional wooden methods.
Steel tubing is available in many sizes and cross
sections. A reasonably well-stocked supplier should have
square tube in a variety of sizes from half-inch to 4-inch.
Rectangular tubing is available in sizes like 1×2 inches,
1×3 inches, 2×3 inches, and so forth. Other useful
shapes are angle iron, which has two sides and is shaped
like an L, channel, which is U-shaped, flat bar, which is
one flat piece and round bar, which is a solid round
shape. Round tubing is hollow on the inside, which
makes it different from round bar. Round tubing and
steel pipe are not the same thing. Black steel pipe used
in plumbing is generally much thicker than the tubing
meant for welding structures. Even so, black steel pipe
is frequently used in constructing scenery.
GREEN IDEAS TIP BOX
When wooden scenery is struck, most nonstock
parts wind up in the trash, but with steel framing,
no part is too small to be recycled. Even small
scraps left over from cutting parts to length during
construction can be collected and recycled. So even
though it may seem counterintuitive, some messy
steel scenery can be greener than some wooden
scenery.

Get Illustrated Theatre Production Guide, 2nd Edition now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.