Assuming you would like to know how to cut a fender on a car:
There are a few reasons why you might want to cut your fenders. Maybe you're going for that rat rod look, or maybe you're just trying to fit wider tires on your ride. Whatever the reason, cutting your own fenders is not as difficult as it may seem. Here's a step-by-step guide on how to do it.
1. Park the car on a level surface and pop the hood. Disconnect the negative battery terminal to avoid any accidents.
2. Using a measuring tape, mark where you want to make your cut. It's best to err on the side of caution and make your markings a bit further away from the edge of the fender than you think you need - you can always trim off more later if necessary. Use chalk or something else that will easily wipe off so as not to damage the paint job.
3. Drill pilot holes at each end of your markings using a 3/16 drill bit. These pilot holes will help prevent the saw blade from wandering as you make your cuts.
4a). If you have access to an air compressor and an air-powered cutoff tool, this is by far the easiest way to make clean, straight cuts in metal. Put on safety goggles and ear protection, then attach the cutoff toolto the air hose and turn it on full blast. Line up the blade with your pilot holes and start cutting!
4b). If you don't have access to an air compressor, don't worry - there are other ways to get the job done ( albeit not quite as easily). You can use either an electric handheld cutoff tool or even just a good ol' fashioned handsaw - whichever you feel more comfortable with. Just be extra careful when making your cuts so as not to damage anything else on the car ( like wires or hoses that might be hidden behind the fender ). And again, go slowly at first until you get a feel for how deep of a cut you need to make . . . it's better to have too little material removed than too much!
5). Once all four cuts are made, gently bend back the flap of metal created by each cut until it breaks off completely . This will give you nice clean edges without any sharp corners or jaggedness .
6). Finally , smooth