Tin snips go by quite a few names, including aviation snips and shears. These are a class of sheet metal cutting tools that are highly useful for workers and craftsmen in a number of industries, including but not limited to roofing.
So what exactly are they, and why does it matter?
What Are They Used for?
Unsurprisingly, tin ships or sheet metal shears are generally used for making cuts through sheet metal. As you can imagine, roofers that use sheet metal need a variety of tools to manipulate, size and shape their medium. Sheet metal shears are only one class of these. They’re highly useful for making both straight and curved manual cuts through a variety of sheet metals, including stainless steel, copper and tin (hence the name tin snips.)
Generally speaking, if you are familiar with regular old scissors, you’d be able to identify sheet metals shears on sight. They are metal tools that consist of two levered handles joined at a central fulcrum that are used to operate jaws. The difference lies in the fact that their jaws are short and compact and they have longer handles to exert a maximum amount of leverage when executing cuts. In that respect, they are fairly simple tools that retain a lot of value.
Why Shears When There Are More Efficient Options?
One of the greatest things about tin snips is in their versatility. If you were wondering, there actually are more efficient options for cutting through sheet metal. After all, as you can imagine, your forearms can get sore fairly quickly when you’re cutting through a large amount of sheet metal manually, even with a compound advantage (see below) so what makes shears a must have tool when there are other more efficient options?
In a word, the answer is versatility. Sheet metal shears are smaller, lighter and more portable than many other sheet metal cutting tools. For workers that are actually on a roof and not just making cuts on the ground, shears are light, comfortable to use, and able to reach into places where larger tools would be impractical.
In addition, metal shears are able to make very precise cuts in areas with very limited room, into which other tools cannot reach. Need to clip off a little piece of metal along the edge of a sheet? Need to make a quick alteration to the end of a sheet before folding it to make a seam? Need to cut a sharp angle in the profile of the metal? Sheet metal shears are excellent for all of these.
Simple Vs. Compound
Some tin snips are very simple tools that consist only of handles attached to jaws and joined by a pin at the center. There are other metal snips that are known as compound snips (which are sometimes called aviation snips). These consist of the same basic components, except in this case there is another compound arm attached to the handles of the snips.
The operation of simple tin snips is very straightforward. The articulation of compound snips is another story. Have you ever seen pruning shears that have a compound arm attached behind the jaws as well? The principle of operation is the same here.
Yes, the longer handles magnify the forces that you can direct through the handles into the jaws in order to cleave the sheet metal, but with the extra leverage of another arm, this effect is compounded even more – hence the name, compound snips. It’s not just about reducing fatigue, though. One of the greatest things about compound snips is that some of them are able to cut through thicker gauge sheet metal than simple snips.
Straight and Offset Handles
If you clicked on our link to tin ships at the top of this article, you may have noticed that not all of them look exactly the same, and not just on the grounds of whether or not they are simple or compound snips. Many of them are made with straight handles whereas some are made with offset handles that sit above the location of the jaws.
Tin snips are great at making precise cuts in sheet metal. That is probably the most valuable aspect of their utility. They are also useful for making long cuts through sheet metal, should you need to. However, when you’re going to make a long cut through sheet metal, especially a straight one, a pair of snips with offset handles is the way to go.
You see, when you make a long cut through any stiff material (not just sheet metal) the material is going to get in the way of your hands, and thus, in the way of the operation of the shears, as you pass through it. Sheet metal, however, is more jagged and unforgiving than many other media, and so the solution lies in the alteration of the tool.
Thus we have shears with offset handles that are great for making longer, straight cuts in sheet metal because the handles lie about the line along which the shear’s jaws cut. Therefore, when you use a pair of sheet metal shears with offset handles, like the Stubai Pelican Snips, your hands won’t get in the way once you pass cutting through a certain point of the sheet metal.
I Can Only Cut a Curve One Way!
There is something else to keep in mind when you’re using manual tin snips. Just about any pair of snips can cut a long, straight line in sheet metal. Some tin snips are designed to cut curves in sheet metal, like the Stubai Circle Snips, which is useful for creating rounded or circular cuts. It all depends on the specific needs of the individual jobs. However, what tin snips can’t do is cut both a straight cut and curves in both directions.
Actually, tin snips are usually designed to cut straight or to cut straight and to curve, but only in one direction. That makes selecting the right pair of snips a little more complicated than could be hoped, but luckily for you, there is one relatively easy trick to keep in mind, just in case you aren’t sure which direction your snips will cut in.
Take a look at the pair of snips in question, paying careful attention to the lower jaw of the snips. Look at how the jaws come together. They have to lay alongside each other in a given fashion, and the snips will always cut a curve in the direction of the lower cutting blade. That’s a nearly foolproof method for identifying just how a pair of snips will cut through sheet metal, but if you need a more foolproof method, see the next section.
My Handles Are Colored
Let’s say you’ve picked up a pair of tin snips from someone else, and you aren’t familiar with them. You might have noticed that the snips have colored handles. Maybe you never took notice of it before, but there’s a fairly good chance that all of your handles are colored and you didn’t notice it before. That might be because all of your tin snips are the same color – but they’re colored this way for a reason. It’s one of the methods by which you can tell which way a pair of tin snips will cut.
- Yellow handles: Perhaps every pair of tin snips you’ve come across has had rubberized yellow handles. That wouldn’t be too unlikely. Here’s what it means, though: these snips are designed for making straight cuts through sheet metal.
- Green handles: On the flipside, tin snips with green handles are designed to cut not only straight but also to the left.
- Red handles: Sheet metal shears that have red colored handles can also make straight cuts, but they’re designed in such a fashion that they can also cut curves to the right.
One thing to remember is that it is very difficult, nearly impossible for a right-curving pair of shears to cut to the left, and vice versa. If you need to make cuts curving away to both directions, it’s worth it to have more than one pair at your disposal, or some other type of cutting tool. Most snips on our website are offered in pairs of right and left cut at a discount.
In addition to choosing between a compound pair of snips or a plain pair and making choices based on the ease with which you’ll be able to make cuts, here are a few more considerations to take while you’re learning about them.
- Blade hardness: The efficiency with which a pair of tin snips will cut through sheet metal and the life span you can expect from it are directly proportional to the heat treatment that has been given to the jaws. The way the steel has been treated and hardened will vastly impact both of these things. The harder the jaws on a pair of snips, the more expensive they will be, generally speaking. It’s worth it, though, because a pair of snips that hasn’t been properly heat treated will not cut efficiently, and worst of all, will wear down or fail before its time.
- Serrated or non-serrated edges: You can also choose between shears that have jaws with either a serrated or a straight edge. When it comes to serrated jaws, they grip the material better and make it a little bit easier for you to cut through it. However, smooth jaws might be more valuable for one specific reason. When you use serrated jaws, the little cuts left along the edge of the sheet metal form a tiny stress riser. Over time, and when subjected to repeated stresses, the metal can tear or crack at those points.
These are some of the most important things to be aware of when you’re looking through a collection of tin snips such as the ones we carry at John Stortz & Son. We’re of the personal philosophy that it’s best to buy quality once, especially if that quality lasts you a lifetime. That way, you won’t need to be pouring money into new tools every time a cheap pair fails you.
That being said, cutting snips are not the only sheet metal cutting tools that we offer here at Stortz & Son. Some of the following types of metal cutting tools are equally useful, if not more so.
Edge Distortion a Problem? Try a Nibbler
If you’ve ever used a pair of tin snips, you may have noticed that along the cut edge of the sheet metal, there is a little bit of distortion. This is because of the shear force that the snips apply to the metal as it is being cut. Sometimes distorted edges can be bent or folded over neatly. Sometimes they can also be deburred. However, there are times when distortion along the edge is unacceptable.
At times like these, a tool like a nibbler might come in handy. Nibblers are tools that remove a thin kerf from the sheet metal, a little bit like a saw. They leave a rough edge that may need to be deburred, but they produce a cut through sheet metal with no distortion, like this Draco Shear for example.
Slitters: For Heavy Duty Coil Cutting
Additionally, there are tools known as slitters that are great for making long, straight cuts through sheet metal. In some ways, slitters are even more precise than shears. This is because they are designed to cut through an entire coil of sheet metal in order to form precisely measured segments. The principle is the same but the application is slightly different. Oftentimes initial cuts are made with a slitter and then final cuts are made with snips.
Don’t Miss Out on The Rest of Our Collection
Here at Stortz & Son, we don’t just sell high quality metal cutting tools for sheet metal roofers. We also sell a top-flight selection of the highest quality seamers and hand seaming tools, sheet metal benders, hammers, decoilers, and much more. Just get in touch with us at 888-847-3456.