In the not-too-distant past, people relied on the traveling tinsmith – also referred to as a “tinker” – to cut and repair most anything made of metal. But today DIYers have access to numerous tools, including metal snips, that allow us to do the cutting ourselves. Granted, cutting metal by hand with snips can be tricky. Workpieces can be stiff and difficult to maneuver, the edges you create during the cutting process are sharp, and the snips can often get in the way while you’re cutting. But take heart: By learning about different types of snips and practicing a few basic cutting techniques, you can quickly master working with sheet metal and duct work.
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Snips of all sorts
A hundred years ago, snips resembled extremely beefy scissors forged from steel. They got the job done, but it took a lot of brute hand strength to initiate and complete the cut. Thanks to revised handle and blade designs, today’s snips make cutting far easier.
Because it can be difficult to create a curved cut in stiff metal, snips are specially designed to make the task easier, and a color-code system lets you know what type of cut the snip is built for (see photo, p. xx):
• Green — cuts clockwise curves
• Red — cuts counterclockwise curves
• Yellow — cuts straight lines
Modern snips incorporate an additional pivot point into the levering action. These cutters (referred to as compound snips) drastically magnify your gripping force and allow you to cut 16-gauge sheet metal with ease (see photo, p. xx).
Compound snips (also known as aviation snips) come in two basic handle types: offset and straight. With offset snips, the cutting blades are positioned below the handle so your hand is above and away from the workpiece (see photo, p. xx). Straight-handle snips have blades that are in line with the handles.
Metal Snip Cutting techniques
Now that you know which snips to use based on the direction of your cut, a few basic techniques will help you to conquer almost any sheet-metal-cutting task.
• Straight cuts: Long straight cuts are best made with compound offset snips. Open and close the jaws of the snips completely to maximize the cut length. As you cut, one side of the sheet metal will tend to ride up and over the lower jaw. Roll this piece back and to the side as you go to keep it from getting in the way of your hand or from jamming the snips (see photo, p. xx).
• Curved cuts: Depending on the access you have to the workpiece, you’ll often need to use a combination of both left- and right-cutting snips to cut curves (see photo, p. xx). If obstructions in a work area prevent you from completing a cut with one pair of snips, switch to the other and try cutting from the opposite direction.
• Cuts in ductwork: When cutting round ductwork, there are a few tricks to keep in mind. If you need to make a cut in the middle of the duct, mark and cut the hole before snapping the ductwork together. Punch a starter hole into which you can insert the snips, and slowly cut along the line (see photo, p. xx). If your cut reaches the duct’s thick locking seam, position the metal deep into the jaws before applying pressure. If, however, you only need to trim a bit from the end of a round duct that’s already snapped together, use curve-cutting snips.
The next time you need to trim some light-gauge metal, grab your trusty snips and go to it. With a little practice and the right tools, you’ll be able to cut metal almost as easily as paper.
Sources
Milwaukee, 800-729-3878
Irwin, 800-464-7946
Apex Tool Group (Wiss snips), 800-548-8883