How to Cut Thin-Gauge Steel

At Buy Metal Online, our free cutting service means you can order exactly the amount of sheet metal you need for the job. But we know that in some cases, such as when working on smaller-scale craft projects, you may need to cut your metal again at home. So, what’s the best way to slice through sheet metal to get the precise size you need? The answer depends on many factors, including the type and SWG (thickness) of material you’re working with. This post will help you decide on the best method of cutting for jobs using relatively thin steel of around 14 SWG or thinner. If you’re unsure about SWG (steel wire gauge), check out our guide to SWG.

Safety First

Cutting metal can be a dangerous job. It’s noisy, and in most cases, produces shards of hot and sharp shrapnel. For this reason, many people prefer to have their metal cut by a professional. If you’re still determined to DIY, please bear these important health and safety precautions in mind:

  • Carefully read the instructions on tools, and the safety advice which is usually printed directly on to blades and cutting discs.
  • Always wear hearing protection, safety gloves, goggles and a face shield, and ensure the same for anyone nearby.
  • Make sure every single centimetre of exposed flesh is covered by clothing or safety gear.
  • Never touch metal straight after cutting as depending on the method used, it could be very hot. Always allow it to cool down first.
  • Ensure no flammable materials are in the vicinity, in case of flying sparks.
  • Keep your gloves on before and after cutting; the edges of cut metal can be very sharp.
  • Remember to clamp metal in place before beginning to cut it.
  • Quickly clean up any shavings or small pieces of metal left on the floor after you’re done as these can be very sharp.

Hacksaw

The hacksaw is a handy way to make quick, straight cuts to relatively thin steel. The shape of the cut is limited by the shape of the saw, however, and hacksaw cuts can be a little rough. It’s fine for straightforward, shallow cuts, but nothing too deep or complex. You can neaten up a hacksaw cut by sandwiching the metal between two strips of masking tape, but if you’re looking for a cleaner edge or a curved shape, this might not be the best method for you.

Tin Snips

Tin snips (AKA aviation snips or compound snips) are a really useful tool for cutting straight or curved shapes into very thin metal. At first glance, they look like a pair of pliers, and can be used to snip through metal like scissors through paper. The snips tend to come with colour-coded handles which indicate the shape of cut to be made: yellow is for straight snips, which cut in a straight line, whilst red snips cut in an anti-clockwise (left) curve and green snips cut clockwise (right) curves. Snips are great for cutting through wire mesh or steel with an SWG of 24 or thinner (remember that the higher the SWG number, the thinner the metal).

Nibbler

Aviation snips are fine for short cuts, but if you need to make a longer cut into your sheet steel, it might be worth investing in a nibbler. A nibbler is a handheld power tool designed to cut through steel. Different models are capable of cutting through different thicknesses, but a decent nibbler can usually easily cut through steel of up to 14 SWG. Although this tool doesn’t produce sparks, it will punch tiny, sharp chunks out of the metal, so do be mindful of this.

Angle Grinder

If you’re looking to make quick, efficient cuts to your steel the answer could be an angle grinder. This classic power tool takes a wide variety of blades, and it’s crucial you choose the right one when working with metal, called a ‘metal cutoff wheel’. It’s not always easy to be accurate with a grinder, so while this is a great method for speed, it’s not ideal for where neatness is key. Angle grinders are very noisy and definitely give off sparks, so follow instructions and health and safety guidance carefully.

Bench Shear

Just like a classic cutter-style guillotine slices through paper, the bench shear cuts through metal with the pull of a lever. Available in straight models for simple lines and ‘throatless’ models, designed for creating curves and more complex shapes, the bench shear is a staple in many metalwork and jewellery-making workshops. If you’re regularly cutting relatively small sheets of metal, this could be an essential piece of kit for you.