With the aid of a straight edge and a sharp knife score both sides of the aluminium sheet.
Best way to cut aluminum sheet metal.
Clamp the sheet metal in place on your work table to hold it in place while you work.
This weakens the aluminium and creates a fracture line.
There are two ways to cut round ducts.
They don t cut curves well.
Sheet aluminium can be cut without the need for a guillotine or tin snips which tend to deform the metal.
An angle grinder fitted with an abrasive metal cutting disc works well to cut all kinds of metal including bolts angle iron rebar and even sheet metal.
Place the fracture line over the edge of a table and bend the overhang slightly downwards.
Cutting aluminum sheet metal with a hammer and chisel is relatively straight forward line up the edge of the chisel along the line you wish to cut and strike the chisel with a hammer.
Using a softer piece of material such as wood as a backer will allow the chisel to push through the metal and prevent wear on the chisel s tip.
Instead we recommend using a diamond blade that s rated to cut ferrous metal.
First if you want to cut a duct near the middle and use both ends mark and cut the duct before snapping it together.
Straight cutting compound snips work best for cutting thick or doubled up sheet metal.
Place the sheet metal on top of the workbench and lay out your pattern using a tape measure pencil and straightedge.
But the discs wear down quickly cut slowly and shrink in diameter as you use them.
Tin snips are primarily used for cutting thin sheet metal like tin aluminum brass and thin gauge stainless steel.