How to cut metal with a reciprocating saw
Reciprocating saws fitted with the correct metal cutting blade make easy work of sawing through bolts, rods, rebar, pipes, profiles, and nails in studwork.
Reciprocating saws cut by the blade travelling in a backwards and forwards, push- pull movement. Many tool models include an oscillating setting which enables the blade to also travel in a movement running perpendicular to the cutting motion- this means that the blade completes an oval cutting motion; this is exceptionally useful when using a reciprocating saw to cut through wood, however, this is best switched off when cutting metal to fully utilise the ‘straight’ cutting capabilities.
These types of saws are really easy to adapt to all types of metal cutting projects due to versatility of the orientation when inserting the saw blade; the blade can be inserted with the cutting teeth facing downwards or upwards and in most modern saws the blade can be inserted in four positions to enable flush cutting and ease of use regardless of operating position. Reciprocating saws are also fitted with a ‘shoe’ that can be adjusted to increase or decrease the available cutting area of the blade; this helps extend the life of the blade and control the depth of cut. The shoe can also be used as a fulcrum to gain purchase on the material being cut and to increase control over the reciprocating action of this power tool.
Tips for cutting metal using a reciprocating saw.
- Eye and ear protection must be worn when using a reciprocating to protect the user from injury from flying offcuts and chips. Sturdy gloves are also advised to protect against cuts.
- Select the correct blade for the metal being cut. The recommended blades for thin metal are those with 20-24 teeth per inch, for a medium thickness of metal between 10-18 teeth per inch, and for very thick metal a blade with around 8 teeth per inch is recommended. A Bi-metal saw blade set that contains a selection of blades suitable for a range of commonly performed projects is a worthwhile investment.
- Choosing a longer blade is useful when flush cutting as it will bend to enable a greater proportion of the cutting edge to ride flat. Cutting thinner materials with a smaller blade will help limit ‘waggle’ during use; usually the blade should only be a couple of inches longer than the depth of cut required.
- Insert the blade into the saw in a way that that best suits the application. For example; if cutting through a material that is flush to the floor, it can be useful to insert the blade with the teeth facing upwards and then switch the orientation of the tool (flip it upside-down) so the handle does not get in the way.
- Setting the saw to a slower speed than for wood cutting will extend the blade life and provide more control and precision. Adjust the shoe to ensure it is set at the most appropriate point on the blade.
- Place the blade where the cut will be, using the shoe as a pivot or fulcrum will help guide the blade until it gains purchase in the metal. Slowly squeeze the trigger and keep a firm hold on the tool housing.
- Changing the cutting angle by lowering or raising the trigger hand (in relation to the workpiece) can speed up the cutting time.
- When the cut is complete, let go of the trigger and withdraw the blade back through the cut.
Prolonging reciprocating saw blade life.
If a saw blade becomes buckled it can be easily straightened by placing on a flat surface, put a flat piece of wood over the damaged area and hit the wood a few times with a hammer- be careful to not damage the teeth.
Blades that have become too worn to cut metal can often be repurposed for use cutting plastics.