The Roofer’s Guide to Metal Snips

When installing a new roof, you want to ensure that it's high-quality and durable. You're thinking of different materials to work with, and you decide metal is the right choice. Great decision! Metal roofs are not only durable but trendy as well. 

You'll need safety gear like protective gloves, safety goggles, long sleeves, and pants. Perhaps most importantly, you'll need a good pair of snips.

A good pair of razor-sharp snips will last years, and there are several factors to consider when purchasing metal snips: cut, hardness, blade type, and roofing material are all important to consider when choosing the right pair of snips for you.

Cut Orientation -- Left or Right Cut

Cutting curves into metal roofing can be tricky. Luckily, most domestically produced tin snips have color-coded handles to help the cutter choose cut orientation.

Red snips indicate snips that cut straight, and to the left (comfortable for right-handed users). Green snips indicate snips that cut straight and to the right (comfortable for left-handed users). Yellow snips indicate snips designed for straight cutting only. 

It's important to remember that the snips will always cut a curve in the direction of the lower blade.

Straight or Offset?

The angle at which the handles are offset from the cutting blades will determine which types of cuts are easier and which are more difficult. For example, handles that are offset 40 degrees to the right of the blades can be used to cut in tight corners towards the left.

Some snips have handles offset at 90 degrees from the blades. This works well for cutting in tight places where your hands may not fit. 

Regular aviation snips work great for dead-on cuts of material. Usually, these snips have narrower blades, which allow for cuts in tight spaces and curves. 

Alternatively, offset snips are great for making long, straight cuts. The elevated handles prevent your hands from making contact with the materials. These snips can still be used for curves, albeit wider curves. 

Blade Hardness / Durability

The hardness of snips determines their lifespan and ability to cut different types of metal. The Rockwell HRC scale is typically used to determine the hardness of steel. Snips usually fall between HRC 56 and 65.

As the hardness approaches 65, the snips are more able to work through harder material, such as thicker steel. You will also be paying a premium for those hard snips. 

It's important to consider the type of metal you'll be cutting through when selecting a pair of snips. The hardness that approaches 65 may not be necessary for thinner tin sheets or other types of softer metals. However, if you plan on cutting stainless steel or harder metals, a hard pair of snips is necessary.

Blade Type

Another consideration when cutting hard metals is the type of blade on your snips. 

Serrated blades are great for gripping and slicing those harder metals, such as stainless steel. These blades also work best for thicker or layered sheets of metal and generally require less force to create a cut. 

Smooth blades are ideal for soft metals, such as zinc, copper, or aluminum. If serrated blades are used to cut through softer metals, they will leave a rough edge where the blades stick to the metal. These rough edges often become a liability down the line, and tears in the metal often occur at these edges. 

Accordingly, serrated blades work well with thicker metals, because they cut more easily and will not distort the material as much. 

Specialty Snips

There are a number of specialty snips for unique circumstances.

Pelican snips, for example, have a slight handle offset, and long blades for creating long, straight cuts. Because of the offset, your hands are removed from the material. These snips aren't ideal for curves, as the blades are long and the offset handle makes the angle of the cut more difficult to control. 

Circle snips are gently curved and typically have smooth blades to create a well-proportioned and consistent radius. These curve-cutting snips are perfect for carving out and finely detailed eave. 

Air Shears

Suppose you are cutting in bulk with a thicker-gauge metal. You could grab your handy pelican snips or serrated blade snips and go for it. However, air shears may be the right way to go in this case.

Air shears use a highly pressurized stream of compressed air to cut metal. Typical air shears on the market can handle relatively thick sheets of metal and often work on harder metals as well. Many air shears come with an offset handle, to assist with angled cutting and cutting at an awkward angle.  

Some air shears include a variable speed trigger. This allows the cutter to control the speed at which air is forced from the shear. There are also air shears with head swivels to improve cut precision. With a variety of different available features, air shears can vary dramatically in price. 

Corrugated Metal and Nibblers

I know what you're thinking: "What about corrugated metal? How would I use snips to cut that?" And it's a great question. 

The problem with cutting corrugated metal is that it isn't flat. In order to cut it with snips, you would have to cut up, down, and right angles. It doesn't make sense. This is when nibblers apply. 

Nibblers typically use a punch and die mechanism, meaning the tool literally punches the metal with a protruding blade at a fixed linear point. Accordingly, nibblers do not create the smoothest of cuts. When using a nibbler, be mindful of the semi-circular shavings that the tool creates as it cuts. 

These metal pieces are sharp enough to injure, often causing scratches in flooring and other surfaces with which they come into contact. It's important to ensure the shavings are contained in the workspace when possible. Many users employ magnets to keep their workspaces nice and tidy. 

The Right Choice for You

When shopping for metal cutting tools, there's a lot to consider. Will you be cutting straight lines or curves? Which kind of metal are you cutting? Are long, straight lines your goal, or are you finely detailing your eaves or roof edges?

Whether you're cutting intricate patterns or bulk slicing sheet metal, the right pair of snips is out there waiting for you