Some automotive parts require a square pass-through hole in either a sheet metal panel or other metal component. Generally, punching a square hole in sheet metal requires a mechanical punch and a square punch and die set. This is an expensive tool, especially if you only need to punch one or two holes. An alternative tool is slower than a mechanical punch but is cheaper in cost and creates a clean square hole in a piece of sheet metal. Actually the preforated metal sheet is always used in the metal basket and stainless steel filter tube. 

4.Take apart the square punch as described in the operating manual of the punch. Slide the mandrel of the square punch through the pilot hole you drilled through the sheet metal and reassemble the manual square punch.

5. Match a socket from the socket set with the hex nut located on the top of the square punch, attach the socket to the 3/8-inch ratchet and slide the socket onto the hex nut.

6.Place the adjustable wrench onto the bolt head of the manual square punch and turn the ratchet clockwise to tighten the mandrel of the punch. Continue tightening the mandrel until the square punch pops through the sheet metal and creates a square hole in the sheet metal.