Things You'll Need
Metal drill bit
Sheet metal is easy to work with and is popularly used in metal fabrication. The most complicated part in the sheet metal fabrication process is opening up a slot in the sheet metal. There are many options for doing this but most will require very expensive industrial machines, like a laser cutter. Luckily with more accessible tools you can cut a slot in sheet metal without needing to break the bank.
Place a piece of plywood on a table or the floor. Make sure that when you are drilling into the sheet metal you stop at the plywood or you will damage the table or floor.
Clamp the sheet metal to the plywood. Make sure it is completely on the piece of plywood so the sheet metal does not get bent when you are cutting the slot.
Mark the shape and size of the slot you want to cut in the sheet metal using the marker.
Drill a hole over the marked area on the sheet metal. Make sure you are using a drill bit for metal surfaces and always select a drill bit that is slightly smaller than the mark. Place pressure on the drill to make sure it does not move out of place as you work.
File down the hole to remove any sharp edges. Keep filing down the hole until you are satisfied with the size of the slot.