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Circular saws work on the same principle as a mitre or chop saw, however, a circular saw is not fixed to a cutting plinth; this gives complete freedom over the cutting movement to enable freehand straight and gently curved cuts to achieved. As with most power tools, models vary in price depending on extra features incorporated to improve the user experience. For occasional use a standard basic model will adequately perform metal cutting applications, however, for more frequent or robust projects it will be worth investing in a heavy-duty model. When using a circular saw for cutting metal it is important to ensure it has an enclosed motor housing to protect the motor from damage caused by metal chips.

Circular saws are held with both hands to support and guide the blade through the workpiece, the saw is always used in a ‘pushing away’ motion with the rear of the blade covered by a guard that moves to surround the blade in response to the position of the workpiece; the top of the blade is covered by a fixed guard. Most models have an additional handle to enable the best hand positioning while working and a guide rail system to line up with cutting lines.

Choosing the correct blade is important to maintain safety and to ensure an accurate cut. Only blades and discs specified for cutting metal should be used. These professional blades are perfect for cutting through aluminium, copper, lead and other non-ferrous metals; while these diamond cutting discs will make light work of cutting through stainless steel.

Tips for cutting metal with a circular saw.

• In addition to standard safety equipment such as eye, hand, and ear protection, it is also recommended to wear long sleeves to protect skin from hot and sharp metal chips that will fly from the blade at high speed.
• Before connecting the saw to a power supply, select the correct blade for the project and adjust the circular saw settings to ensure all fittings and attachments are correctly aligned and tightened. The cutting depth of the blade should not be set to exceed ¼ inch (6mm) beyond the thickness of the metal.
• Mark the cutting line with a marker or scoring scribe and firmly fix the workpiece with clamps. Ensure the blade has clearance on the underside, if it does not then the metal can be mounted on rails or across two work horses.
• Connect the power, then align the blade with the proposed cutting line without the blade being in contact with the metal edge, use the cutting guides to help. Slowly depress the trigger to power up the blade, once it has come up to speed, carefully slide the blade into the metal- do not rush or force the cut, just let the blade do the work.
• Regularly apply cutting fluid as the saw travels the length of the cut to reduce heat and allow a clean cut.
• Once the cut is complete, disconnect the power supply to the saw. Do not touch the cut edge or the blade after cutting as they will be hot enough to cause a burn.

Bandsaws are a power tool that have a looped metal cutting blade tensioned over 2 pulleys. The top pulley retains and guides the blade, while the lower pulley varies the speed. The blade runs in one direction rather than with the ‘up and down’ movement of a jig saw.  Bandsaws are not suitable for cutting very thin sheet metal; a rule of thumb suggests the metal to be cut should be thicker than the depth of 3 bandsaw blade teeth, however they are excellent for cutting thin walled profiles such as box and angle.

Blades are available in different widths suited for different cutting requirements; thicker blades work well for thicker metal stock and straight cuts, whereas a thinner blade is better suited to cutting curves. Blades with a higher tpi provide a smoother cut edge whereas blades with a lower tpi make light work of cutting through thicker metal stock.

Bandsaws are available as cordless units, bench top models, and as freestanding floor models.  As with most power tools, the range of extra features increases from standard settings on smaller DIY models to a fully comprehensive range of additional features available on the more professional models, extra features may include mitre cutting settings, more variable speed settings, and hydraulic descent in addition to standard manual descent. Bandsaw speed settings are measured in either metres per minute (mpm) or the more standard revolutions per minute (rpm).

Tips for cutting metal with a bandsaw.

• Ensure correct PPE including eye and ear protection is worn.
• Mark or score the cut line if necessary.
• Ensure that the blade is suitable for cutting metal and that it is correctly fitted and tensioned.
• Make sure all blade guards are in the correct position and free from defect.
• Adjust all settings for the type of cut being performed; such as speed and mitre angle for example.
• Connect the power and make sure all cables are out of the way of the blade, then start the machine.
• When using a bandsaw set in the vertical position, cutting is achieved by resting the metal on the plate and pushing it towards the blade while maintaining pressure. The blade can pass completely through the workpiece or the workpiece can be simply withdrawn, rotated and pushed towards the blade again to make additional cuts.
  • If cutting an intricate design, it is advisable to make a series of relief cuts to reduce any binding on the blade.
  • When cutting curves, it is best to start at the shallowest angle of the curve and work towards the steepest angle to reduce the risk of the blade veering off from the cut line. If both ends of the curve are shallow, make a cut from each end until they meet at the middle.
• For cuts using the hydraulic arm capabilities of some bandsaw models, place the metal on the support table and ensure it is firmly held against the rear guard, lower the arm to move the blade downwards through the workpiece.
• For cuts using a cordless bandsaw; ensure the workpiece is secure, line up the blade to the intended cut line and lower the blade into the metal. Once the cut has been made, stop the blade and withdraw.
• If the blade begins to stick or bind, stop the blade and apply some wax stick directly to the teeth of the blade.

Hacksaws are a hand tool that is a very versatile addition to any workshop. Hacksaws work by simply moving the blade through the metal backwards and forwards in a regular ‘sawing’ action. The C shaped handles are relatively cheap to buy and the wide range of blades available enables a wide range of profile thickness and metal grades to be cut easily. The handles range from basic varieties that simply, yet securely, hold the hack saw blade in place through to professional varieties that have easy to use features such as; thumb dial tensioners in the handle to provide 150kg or 30,00 psi blade tension, adjustment to accommodate 250mm or 300mm blades, and  secondary blade positioning to enable 45° blade angle for flush cutting or 90° for general cutting.

Hacksaw blades are selected by choosing the correct tpi (teeth per inch) for the type of metal that needs to be cut. The higher the tpi, the more aggressive the cut. The teeth are configured to face towards one end of the blade and the blades can be mounted in the handle with the teeth facing forwards or backwards- the benefit of this is that the power of the ‘towards’ or ‘away’ stroke can be focussed to provide the user with the best cutting ergonomics. Many metal workers prefer to focus the main cutting stroke as the ‘away’ stroke as this provides a clearer view of the cut because the chips are moved forwards during operation.

Hacksaw blade tpi recommendations.

Tips for cutting metal using a hacksaw.

• Always wear eye protection and gloves when cutting metal.
• Select the correct blade for the project being undertaken and ensure it is securely inserted in the frame/ handle with the teeth facing either forwards or backwards depending on preference.
• Check the blade is rigid, correctly aligned, and taut.
• Clamp the workpiece or place it in a vice; if this is not possible as the metal is joined to another object, ensure the piece you are not wishing to remove will remain secure once the other piece has been cut off.
• To begin the cut, make a series of one-way strokes against the direction of the teeth – this will create a narrow incision that the blade can sit in. Once the blade has gained purchase in a millimetre or so of the surface, the full forward and backwards sawing action will soon enable the cut off to be completed.
• Try not to rush; a smooth, steady sawing action will provide the best cut and will reduce the likelihood of the blade overheating and breaking. A little machine oil or cutting fluid placed on the blade will reduce friction.

Most home and commercial workshops contain an angle grinder as they are one of the most versatile tools; by simply changing the disc you can quickly and easily perform a range of tasks such as cutting metal, stripping rust and paint, deburring, preparing metal for welding tasks, scoring and cutting stone, tiles, and concrete, and cutting out mortar.

For small or infrequent jobs, an abrasive metal cutting disc can be used on an electric drill with the aid of a backing pad to support the disc; for regular or more heavy-duty applications, a disc cutter or angle grinder will give the best results.

Tips for cutting metal with an angle grinder, disc cutter, and rotary tool.

• The discs rotate very quickly which will results in hot sparks and chips flying off at speed. Eye protection, heavy duty work gloves, protective footwear and ear protectors are all recommended to keep you safe.
• Begin by selecting the disc best suited for your project and check that the maximum rpm of the disc is higher than the maximum rpm of the tool; this will protect against the disc becoming over-stressed and fracturing which can cause serious injury.
• Discs are available in flat, raised centre, and depressed centre presentations. Raised and depressed centre discs are perfect for getting into tight corners and overhangs as they allow for a different angle of entry into the metal; these discs should not be driven too deep as the altered geometry of the disc can get in the way and damage the disc.

Suggested disc types.

• Securely clamp the workpiece near to the intended cutting point or ensure the piece you are cutting from is secure and will not drop or fall during working.
• Check the tool and disc mounting is correctly set up by running the grinder for a minute or so to ensure any balance or fitting problems are discovered before starting work.
• When beginning the cut always present the blade at 90° to the workpiece taking care to ensure the guard is positioned between the worker and the workpiece. Avoid using impact or bumping the disc into the metal and always present the cutting blade where the metal is thinnest- round profiles are easiest as the surface contact is uniform, profiles such as ‘I beams’ and box section should be started at a corner to reduce friction. Do not apply too much pressure, just let the disc do the work.
• The use of a  mill bastard file   is useful after angle grinding to de-burr and smooth the rough cut edge if required.

A jigsaw is a hand-held power tool that is operated by a squeeze trigger in the handle and is designed to cut sheet metal, pipework and wood. As with most power tools, jigsaws vary in the features they offer; for the hobbyist or DIY enthusiast a standard model fitted with the right blade will handle most workshop jobs with ease. For heavy-duty metal cutting, a more robust professional jigsaw would be more suitable as these can cut through 10mm steel and up to 30mm thickness on non-ferrous metals.

Jigsaws are not suitable for plunge cutting metal, however, a hole can be drilled to feed the blade through and then the cut can be continued in the usual way. Jigsaws have good manoeuvrability which makes them ideal to cut quite intricate shapes;, on tight curves it is advisable to make relief cuts to reduce the risk of the blade binding, however, this will only be possible if the cut off side is scrap, otherwise, it may be possible to get as far into the curve as possible then withdraw the blade and approach the curve from the uncut end.

Jigsaw blades have a single row of teeth along one edge of the blade, these are arranged in a small wave pattern from left to right- a blade with 21-24 tpi is recommended for cutting metal and one manufactured with a bi-metal construction will offer the best durability.

Tips for cutting metal with a jigsaw.

• Wear appropriate PPE, this should include eye and ear protection and good quality gloves. The cut off metal will fall, it is prudent to wear sturdy, reinforced toe work shoes or boots.
• Mark out or score the cut lines.
• Securely clamp the workpiece to the work bench. If there will not be sufficient depth clearance for the blade, the metal can be placed on rails and then clamped to ensure blade clearance. Some metalworkers ‘sandwich’ the metal sheet between two thin sheets of wood to add support while cutting- this technique will take longer but will help minimise distortion on soft or thin metal.
• With the power supply turned off, select the appropriate blade and insert it into the saw, ensure it is secure and correctly tightened. This is also a good time to check the settings are correct for cutting metal; this will include making sure the blade is set in a straight down position for metal cutting and not angled forward on the wood setting. If the surface of the metal will mark easily, the shoe of the saw can be covered with masking tape to help protect the surface finish. When all settings are correct, keeping fingers clear from the trigger switch, switch on the power.
• If starting the cut at the edge, press the saw shoe firmly on the surface of the workpiece without the blade touching the metal. Slowly depress the trigger and once the blade is moving, glide it into the workpiece. It is important not to force the speed of the cut and just let the blade do the work. If starting the cut away from the edge of the workpiece, simply drill a hole large enough to insert the blade in and continue as above.
• Once the cut is underway, pause the saw and add a few drops of tapping and cutting fluid to the cut to reduce heat at the blade then continue. Apply cutting fluid as required.
• Move clamps and rotate the work as necessary to gain the best positioning of the saw to achieve the best cutting line.

Pipe cutters are a simple hand-held tool that easily cuts through steel, copper, bronze and aluminium tube sections. The tool is constructed in a ‘C’ shape that has rollers and a cutting blade set within the inside edge.

Some models need to be manually adjusted while cutting to decrease the aperture and others are self-adjusting. The more basic pipe cutters have a fixed cutting diameter and more professional models can cut pipe with a diameter of between 8mm and 35mm.  Pipe cutters are also available in a choice of handled or non-handled, both perform the same cutting action, however, it is a matter of personal choice of which type to use. A range of pipe cutters can be viewed here.

Tips for cutting metal with a pipe cutter.

• Ensure eye protection and gloves are worn.
• Measure the pipe or tube and mark where the cut will be.
• Put the pipe cutter over the end of the pipe and slide it along until it reaches the cut point.
• Tighten the grip on the tools and twist the cutter around the pipe until the blade cuts through. If using a manually adjusted pipe cutter it will require tightening after 3 or 4 turns, however, whichever model is used it will only take a few revolutions.
• Deburr the cut end with a mill file or abrasive paper if required.

Chop saws and cut off saws make a straight cut across the profile at 90° while mitre saws cut across profiles at an angle, however, the directions for using all these machines are the same. Mitre saws, cut off saws, and chop saws have a ‘cutting plinth’ integrated into the design to provide a static cutting area.

Although mitre saws were traditionally used for cutting wood, with the correct blade they can make light work of cutting through steel and aluminium profiles at an angle.

Accessories  such as these mitre saw blades provide easy cutting through aluminium and non-ferrous metals, or these high performance discs  give good results for cutting through steel and stainless steel with precise, clean cuts.

Tips for cutting metal using a chop saw, cut off saw, or mitre saw.

• As with all metal cutting operations, ensure that eye protection, gloves and ear defenders are worn to protect against injury from flying shards and chips of metal.
• If using a mitre saw that has open motor housing, simply tape some thin cloth over the openings and vents to protect the motor from metal chips.
• If sawing through a profile that is hollow or that has a thin wall, such as aluminium angle, it can be advantageous to back the metal with a piece of wood to add support, therefore, minimising the risk of the blade catching on the metal which may cause a deformation in the metal being cut.
• Before switching on the power to the saw, check that the guard is in good condition and set at the correct position, and that all cables are clear from the cutting area.
• Place the workpiece on the table and secure the workpiece using any vice adjusters or mitre locks and ensure it is held tight against the fence to ensure accuracy of the cut.
• One you are satisfied with your machine set up, maintain pressure on the workpiece against the fence then depress the power switch on the saw and listen for the blade to reach full speed before lowering the blade slowly and consistently through the metal. When the cut is complete, hold the saw in the down position and release the power button- keep a secure hold on the workpiece until the blade has come to a complete stop. One the blade is stationary, return the blade carriage to the upright position.

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.

Guillotines cut metal by using 2 blades; one is fixed under the workpiece, the other moves downwards to cut through the metal. Guillotines come in many different sizes and are known by an array of names such as; guillotine shear, plate shear, squaring shear, Beverly, and throatless shear, but essentially, they all utilise the same mode of cutting.

Guillotines are available in mechanical, pneumatic and hydraulic models for use across a wide variety of projects. Hand or foot operated models are a useful addition to the hobbyist or DIY enthusiast as they make light work of cutting through aluminium, bronze, brass, and mild steel without the need for a large workshop or financial investment. For the metal worker needing fast and multiple sheets cutting regularly, a larger CNC pneumatic or hydraulic model would be more appropriate.

The cut edge of the metal may need deburring or finishing after being cut with a guillotine, this can be done with a mill file or an aluminium sanding sheet.

The different types of guillotine are looked at more closely below.

Squaring shear, power shear or guillotine.

This is most commonly used in industry as a hydraulically powered CNC machine, although they are available as foot or hand powered units. Guillotines can have either a fixed or variable cutting angle that reduces the risk of metal becoming trapped in the blades, although setting this ‘rake’ angle will compromise the exact squareness of the cut edge- this can usually be set to between 0.5° and 2.5°.  The force of the cut can also be reduced by adjusting the ‘shear angle’; this alters the rocking action of the blade to increase the stroke- this makes the cut from one side of the metal to the other as more of a scissor action than a chopping action.

Tips for cutting metal using a guillotine.

• Eye protection and gloves should always be worn when cutting metal to provide protection from cuts and metal splinter injuries. Guillotines powered by electricity are incredibly noisy so ear protection should also be used.
• Adjust the settings on the machine by following the manufacturer’s instructions to the desired length of cut, shear angle, and rake angle.
• Ensure that all guards are in good working order and correctly in place. The blade and clamps should be correctly isolated by the guards to avoid entanglement. The force used within guillotines could sever a limb, so do not rush the machine set up or ‘make do’ with any element of the equipment that is not fit for purpose.
• Place the metal into the front of the machine and feed it through until it touches the back gauge then activate the clamps to secure the metal.
• Engage the blade mechanism which may be a key pad, treadle, or lever depending on the machine. The blades will shear off the metal which will drop into the collection chute to the rear of the machine.
• If the metal does not drop out from the machine, do not try to free it manually as the blades may be jammed against the cut off metal, removing the metal may cause the blades to slam closed or the metal to drop suddenly causing catastrophic injury. Switch the machine off and call a qualified engineer to clear the machine.

Throatless shear, Throatless guillotine.

Throatless guillotines have no plate in front of the blade to support the metal and no ‘throat’ to dictate a particular way the metal must be fed into the blades. This configuration makes it easy to manipulate the metal easily into the cutting blades. The blades are raised and lowered into and out of the metal by a hand operated lever.

How to cut metal with a throatless guillotine.

• Ensure eye protection and heavy-duty gloves are worn.
• Mark the metal with marker pen, or a scoring scribe, along the cut line.
• Feed the metal between the blades and lower the lever in small or long drags to make a series of short snips or longer cuts while continuing to manipulate the metal into place; this simple technique allows almost any shape to be cut from sheet metal.

Bench shear.

Bench shears are mounted on the workbench to provide a secure working environment. The lever operated mechanism provides a forceful cutting action. Bench shears can be used to cut out rough shapes and straight cuts in sheet, however, they are not suited to the more intricate cutting that is achievable with throatless shears.

How to cut metal with bench shears.

• Ensure correct PPE is worn.
• Measure and mark or score the cut line if necessary.
• Place the metal between the blades and pull the lever downwards to engage the blades and push it back into an upright position to open the blades.