How to cut metal with tin snips
Tin snips are an inexpensive and invaluable addition to any tool box. For most cutting jobs regular tin snips will be perfectly adequate, but for some projects it is worth upgrading to one of the more specialised blade configurations to achieve better results and perform the task with as little effort as possible.
As a general rule, the larger the tin snip tool, the thicker gauge of metal that can be cut. There are two main types of tin snips available; tin snips, and aviation shears- within each type there are several different configurations available.
The different types of snips are outlined below.
Standard tin snips. This style of tin snip is also commonly called ‘tinners’ and ‘Gilbows’ and are mainly used for long straight cuts. Tinners have a basic construction of two bladed handles being fixed together with a nut and bolt. These are good for cutting thin gauge metal sheet, metal mesh, and other mainly flat metal items.
Types of tin snips available;
- Curved tin snips have curved blades that can perform tight radius cuts in both clockwise and anti-clockwise directions.
- Straight tin snips that cut straight lines with minimum effort.
- Right hand tin snips are suitable for cutting straight lines and cutting off in an anti-clockwise direction. Best suited for right handed use.
- Left hand tin snips are suitable for cutting off in a clockwise direction and for cutting straight lines. Best suited for left handed use.
Aviation Snips. These are also often referred to as ‘compound’ snips. These have 2 pivot points instead of one, therefore, less force is needed to maintain a clean cut. Aviation snips are not designed to make long cuts in sheet metal, but rather to perform more specialised tasks. Compound snips are suitable for cutting through aluminium and sheet metal up to around 24 gauge. Aviation snips are available in a wide range of configurations to suit specific project requirements.
- Vertical snips. These snips have the blades set at a 90° angle to the handle. This configuration enables overhead cuts, or cuts in tight places, to be performed with ease.
- Offset snips. These snips have the blades set at less of an angle than vertical snips and are particularly useful during projects where no free hand is available to move the offcut away from the blade; the offcut moves to the side unaided as the bottom blade is ‘offset’.
- Straight snips are often colour coded with yellow handles, these are the type to use for straight cuts and wide curves.
- Right cut snips are colour coded with green handles, these will cut straight both lines and curves angled to the right.
- Left cut snips are colour coded with red handles and cut straight lines and left angled curves.
Choosing the correct snips.
Although the wide range of tin snips may look daunting at first, it is worth ensuring you pick the correct snips for the project. It is important to ensure the left hand and left cut, or right hand and right cut specifications don’t confuse- remember, aviation snips can be used in either hand to perform their intended purpose; use the colour coded system for guidance, whereas, left and right hand tin snips are intended to be used in either the left or right hand according to their designation. ‘Left hand’ snips cut clockwise while ‘left cut’ aviation snips cut anticlockwise and ‘right hand’ snips cut anti-clockwise while ‘right cut’ aviation snips cut in a clockwise direction.
Tips for cutting metal with tin snips.
When using tin snips, it is important to wear protective gloves as the cut edges of the metal will be very sharp and any slips could result in a deep cut. It is always recommended to wear eye protection to prevent injury from shards of metal that may fly off.
Essentially, tin snips are used in the same way scissors are used to cut paper. It is worth taking the time to mark out the desired cut line with a simple marker pen to make the whole operation simpler, especially as the metal may need to be manoeuvred and moved during cutting.
Clamping the work piece may be necessary for some projects, however, for smaller pieces it is often easier to just hold it.
Most projects will be straightforward and do not require any special techniques; some tips for cutting circles and thicker metal are outlined below.
Cutting a circle.
- Mark out the circle with a marker pen and puncture the metal in the centre of the circle using an old screwdriver or a punch to make a hole large enough to slip the end of the tin snips’ blade in; placing the metal on a folded cloth or sponge to help keep it raised while making the initial slit is helpful. Offset aviation snips and curved tin snips are recommended for this task.
- Make small snips in a gentle spiral shape until the marked-out edge of the circle is reached. If using red handled, (left cut) tin snips, cut in an anti-clockwise direction, if using green handled (right cut) snips, cut in a clockwise direction.
Cutting thicker metal.
- Using straight aviation snips, open the handles wide and place the metal in the jaws where the 2 blades meet. Using a steady but firm force, squeeze the handles closed. Take care to not close the blades too quickly or the metal may ‘jump’ out of the blades creating an unsatisfactory cut or cause an injury.