It's inevitable that many of us are going to encounter our fair share of rusty panels when it comes to building a hot rod, truck, or street rod with 50-plus years of harsh use on this planet. Areas prone to collecting dirt and debris are especially susceptible and tend to be the first spots that start to rust and inevitably chew their way through the steel.
It's understandable that the underside of fenders, which act as huge catcher's mitts for any and all road debris kicked up by the tires, receive the brunt of said abuse. And, since most automobile owners rarely clean the underside of their cars, it's no wonder the debris has a chance to gather and cause such detrimental damage. With a large area of the country under snow during those long winter months, the salt that has a chance to gather in those hard-to-reach places only magnifies the possibility that those pristine Deuce fenders you picked up at the swap meet may actually have quite a bit of rust damage under that seemingly cherry finish.
We ran into that exact situation when we started stripping the fenders on our '52 Ford F-1 project. The truck had been bombed in charcoal black rattle-can and looked pretty straight until the fenders were sanded down to bare metal. With the paint and Bondo removed, it was very obvious that whoever did the bodywork had done a pretty good job simply covering up some trouble areas way back when. Any area that could gather dirt and debris did, and the result was a cancerous patch that would need to be repaired.
Years of constant use and neglect also left the underside of the fenders covered in a nice, rusty patina that would also need to be treated. Given their reputation of solid rust repair options, we contacted the Eastwood Company to help us treat, repair, and add an ounce of prevention to our F-1.
When the rotten section of...
When the rotten section of the rear fender was trimmed away, it revealed a rusty but intact support structure underneath the fender skin. Since this area will be sealed up after the patch panel is installed, the opportunity to treat the rusted area later will not be an option, making it necessary to treat it now.
Masking tape was used to cordon...
Masking tape was used to cordon off the work area, since we didn't want to affect the surrounding area.
The first step was to try...
The first step was to try to remove as much of the rust as possible, and this was accomplished by using the Eastwood Speed Blaster. This tool is great for blasting areas that are either too big to fit in a blasting cabinet or are in hard-to-reach places.
Borrowing some sand from our...
Borrowing some sand from our blasting cabinet, we filled the Speed Blaster and dragged the fender outside to give the rusty area a quick blast. Be sure to do this in an open, clear area, away from the wife's car, the dog, or your kids. Also, try to use it in an area that will be easy to sweep up, as it will leave the surrounding area fit for a beach party.
Within a few minutes, half...
Within a few minutes, half the affected area was blasted clean of any rust. Here, you can see the difference between the blasted and rusty area.
You can see how well the Speed...
You can see how well the Speed Blaster worked at removing 80 percent of the rust. Just to be safe, though, we're still going to treat the area as if it still had a chance to rust further.
For this, we treated the affected...
For this, we treated the affected area with Eastwood's Cold Galvanizing Compound. The nearly pure zinc coating gives the same results as hot-dip galvanizing and will not burn off like other finishes when the patch panel is installed.
The aerosol can makes it a...
The aerosol can makes it a snap to apply the finish over the affected area. One evenly applied 2- to 3-mil coat will do the trick.
With the satin-gray finish...
With the satin-gray finish dried, this portion of the fender was treated and can be set aside for a future patch panel installation.
While on the subject of rust...
While on the subject of rust treatment and prevention, we decided to move under the fender and try out another Eastwood product. Like the patch area, the surface was prepared beforehand-this time with a wire wheel, since blasting the entire fender would require much more work.
Lacquer thinner was used to...
Lacquer thinner was used to clean and prep the surface after the loose rust, scale, dirt, and paint were removed.
Eastwood has a number of products...
Eastwood has a number of products to treat and prevent rust, including Heavy-Duty Anti Rust and Rust Encapsulator. Both are available in either gray or black and in 13.5-ounce aerosol cans or by the quart. Heavy-Duty Anti Rust is a great preventative for those inner areas, such as under the dash and inside the doors that don't have heavy rust problems, but it can't be painted over. Rust Encapsulator, on the other hand, can be covered with most types of topcoats: enamels, urethanes, lacquers, epoxies, and polyester body fillers.
Since we opted to scuff the...
Since we opted to scuff the surface with a wire wheel as opposed to blasting the entire area, Rust Encapsulator was chosen since it can be applied directly over a rusty surface. We blocked off a section to illustrate the difference of the Rust Encapsulator-treated area and the untreated area.
Here's the treated area after...
Here's the treated area after the Rust Encapsulator had a chance to dry. Once the patch panels are installed and the fenders are repaired, the entire underside will receive this treatment before being undercoated to prevent any future problems.