A diminutive sibling of the cabinet-sized cold saw, the cold metal cutting saw is used to cut thin, steel sheet metal. This saw is a lightweight, hand-held saw with a circular blade similar to a circular saw used to cut wood boards. It is less often a table-mounted saw, much like a miter saw, that delivers a more precise cut when working with longer lengths of material. The saw blade of this type of saw is manufactured using Cermet, a ceramic/metallic composite that not only resists heat but will hold an edge much longer than does the tungsten carbide blade that this composite is designed to replace. The hand-held cold metal cutting saw is powerful enough to cut steel sheet metal as thick as .23 inches (6mm).
Cold metal cutting saws are designed to rapidly cut lengths or pieces of zinc-coated, steel sheet metal without heating up either the blade or the material. This cold sawing thus preserves not only the keenness of the saw blade, but the anti-corrosive coating at the edge of the cut. It is also designed to prevent leaving damaging burrs on the metal. The saw is ordinarily equipped with a durable aluminum catcher to collect the swarf (steel particles or sawdust) thus preventing its dispersal over the work area.
Used primarily by sheet metal roofers, cold metal cutting saws enable the efficient cutting and trimming of the thin sheet metal and corrugated iron often utilized in residential and commercial roofing. Sheet metal, actually thinly rolled mild steel -– steel containing less than .3% carbon –- must be kept cold when it is cut. This ensures that the anti-corrosive zinc coating on the sheet metal remains intact at the edges of the cut, thus preventing a premature rusting of the material.
A portable, cold metal cutting saw easily cuts the thin sheet metal used in today’s roofing construction. This material averages approximately .03 inches (1mm) in thickness and is lightweight, durable and reasonably inexpensive. In addition to sheet metal and corrugated iron, modern metal roofs may be manufactured from stainless steel, copper, aluminum or zinc alloys. A cold metal cutting saw, primarily designed to cut steel sheet metal and corrugated iron, is generally unsuitable for cutting any other material. Electric metal shears or nibblers, metal scissor-type shears or circular saws with abrasive blades would be far more effective in cutting these other types of metal roofing.