Unfortunately, over the years, corrosion can appear on a car’s body. And if you don’t deal with it early on, those small “rust spots” can quickly turn into full-blown through rust.
Unfortunately, over time, corrosion can develop on a car’s body. If it’s not treated right away, small “rust bugs” can rapidly turn into through rust.
Let’s be honest — most people don’t have the time or opportunity to constantly care for their car’s bodywork. Especially when the car is older and there are multiple rusted areas. Fixing all of that at a repair shop can get very expensive. You can do it yourself, but that takes both motivation and time. Many people treat their car simply as a means of transportation and ignore small rusty spots. But when corrosion eats through an entire section — like a fender — it looks terrible and eventually has to be fixed.
For those who don’t care much about their car’s appearance, naturally, cheaper repair options are more appealing.
Often, people buy the cheapest body panels on eBay — usually Chinese-made parts that, frankly, tend to rust just as fast. So I’d recommend getting original parts from a salvage yard instead of buying the cheapest aftermarket ones.
If you have some basic body repair skills, you can even extend the life of a part yourself — or find someone who can do it for you. The process isn’t too complicated, and it can save you the cost of a new part or welding work.
I’ve done this myself many times for different reasons. Usually, it was for friends who wanted to improve their car’s appearance cheaply. What’s interesting is that even years later, some of those repairs still look good — no new rust. This kind of repair isn’t like the typical “flipper fix,” where they just fill it with body filler and the rust reappears in a couple of months. This method lasts. Of course, it also depends on the area being repaired — if you can access both sides of the panel, it’ll last much longer. But if it’s, say, a rear fender with access only from one side, it won’t hold up as long.
Now, step by step — let’s take an example of a badly rusted front fender. First, you need to clean off as much rust as possible; any fully corroded areas can be cut out.
After removing all the corrosion, it should look something like this:
In this particular case, it would be easier to replace the fender entirely, but we’re using this just as an example.
If you’re repairing something like a rocker panel or rear fender, it’s best to sandblast the rusted area after cleaning. A simple sandblaster can easily be made at home — it’s quick and inexpensive, as long as you have an air compressor. If you don’t have one, at least treat the cleaned area with a rust converter — apply it several times for better results.
Next, you’ll need fiberglass and polyester resin. For convenience, if you’re working with large holes, apply masking tape first so the fiberglass doesn’t sag when you brush on the resin.
Cut the right amount of fiberglass and apply the resin.
Wait for it to dry — usually about 30–60 minutes. Then trim the excess with scissors or a grinder. After that, apply another layer from the opposite side.
Next come the usual bodywork steps. Rough up the fiberglass surface so the filler adheres properly. At the same time, sand down the edges to make the transition from metal to fiberglass smoother. Remove any dust, apply body filler, level the surface, and then prime it.
After leveling the primer, apply the base coat and clear coat — and you’ll get an excellent result.
What’s great about this method is that the repaired part retains its rigidity. You can even tap it lightly — nothing will fall off. Since there’s only a thin layer of filler, it won’t crack after a few months. The rust is sealed in tight, and for several years, it won’t show through. Of course, the final durability depends on how well the part was prepped. Overall, this method works and lets you fix rust affordably and for the long term — or at least effectively hide it.