Sheik said:
.....Louie's been around many years and I've yet to hear anyone speak negative of him.
.....hmmm louie smells bad....lol (couldn't resist).
As for how to repair the damage.
As many have said, it all depends on how handy you are. If you want it to look like a dog's breakfast, do it Joe's way (sorry joe lol, I don't see any good in slopping anything on anything! lol).
It all depends on how bad, how big, and where the hole is located. If you just want to make it look semi presentable, the BEST way is to cut away all the cancer. Keep cutting until you hit virgin metal. If it is on the relatively flat part of the quarter panel in front of the wheel, CTC sells a flexible metal patch that can basically be bent and shaped by hand. If there is a fold or crease along the front of the panel in front of the wheel (it's better if there is), mark the sheet where that line will fall. Put two marks on it. The simplest way to make a straight crease is to bend it over the edge of a table. If you have a couple of clamps, put a piece of plywood on top of the piece along the edge, and then fold it. You can get a nice straight line that way.
The trick is to get the patch about 1/2" bigger than the hole. Once you get it cut to shape (tin snips will work) you're going to want to pop rivet it into place. To do this you'll need to drill holes every couple of inches around the circumference of the hole. Put the patch inside the hole then mark the locations with a sharpie. Once you have all the holes drilled rivet the piece into place. This will give you a patch that is slightly lower than the existing body work. You want this.
Now get Joe's sloppy stuff (body filler) mix up only as much as you can use in 10 minutes. Don't worry about making it perfect the first time. You can build it up. Mix about a pea sized hardener with about a 1/2 cup of filler. MIX IT WELL, you can't over mix it but you can screw around too long and it'll harden on you.
Using a plastic spatula or even a cut out from the top of a margarine container, putty the body filler onto the patch. You're going to want to build it up so it is just slightly higher than the surround body work. Once this layer hardens (20 minutes or so) you can now sand it level with the rest of the body using a long sander and long strokes. don't worry if it isn't perfect at this point. Just get it close. Now if you want a really good job, you can grind off the rivet heads or just cover them with body filler. If you are good at it, you can feather out the filler so that you can camelflage the rivets.
Here's a basic list of things you'll need:
Can of body filler with hardener
Metal patch just larger than the are you want to fix
Pop rivet gun (a kit runs about 10 bucks at canadian tire)
Coarse and fine sand paper and a length of plywood to use as a backer for the sandpaper (this makes it easier to get a flat surface while sanding instead of waves). Long strokes are the way to get this.
Scrap piece of plastic or plywood to mix the body filler on.
Putty knife, spatula or ?? to mix and apply the body filler.
Drill and bits to drill the holes for the rivets.
Primer and touch up paint in your car's colour.
Tin snips.
A grinder with cut off discs and sanding discs is easiest to remove the rotten metal but isn't necessary.
A palm sander can work as well to sand down the body filler. LONG STROKES!!!