When using metal that is a little bit thicker than sheet tin one can predrill the hole and then install a self-tapping sheet metal screw. These screws have cutting threads on the tip of the screw and act like a small tap when inserting into the hole. They hold tightly and work well. Let s back up for a moment and take another look at nuts and bolts. A tractor in a field can produce vibrations, stresses, and heavy loads that make nuts and capscrews loosen.
Lets examine how to keep that from happening.
Manufacturers have developed a number of devices to keep nuts in place. Special washers, locking nuts, plastic collars, and liquid fasteners are a few of the types we have to work with. Probably the most common thing used on the farm would be locking washers. They are designed to provide a friction point between the nut and part surface. When using these washers on softer metal like aluminum place a plain flat steel washer underneath to prevent damaging the part.