Rust on a Campervan spells trouble and you’re going to want to figure out the extent and remove it as quickly as you can. This article will cover some of the science behind rust, how to identify what kind of rust you have, and how serious it is, and then how to deal with it.
We do this early on in build, working outside in, to make sure our base vehicle doesn’t cause us any issues when we’re mid-build or out on the road. Rust can be thought of as a kind of disease for your campervan and early detection can save a lot of trouble later on. Plus it’s much easier to tackle when your van is empty.
Rust is basically what happens when oxygen, water, and iron (like what your campervan is made of) get together and have a not-so-fun reaction, creating oxidised iron. This reddish-brown material turns the iron into something else completely, which causes corrosion, and the breakdown of the metalwork on your campervan. You know it’s bad when that stuff appears.
Types of Rust
This nasty corrosive force can be categorised into three main types: surface rust, scale rust, and penetrating rust.
Surface rust is the least harmful type of rust and only affects the top layer of your campervan. You’ll usually spot it as bumps and nicks on body panels and if left untreated it can get worse.
So, you want to sort it here, now, tomorrow.
There are a few variations of surface rust, like flash rusting, which can form in hours and be removed with a rust remover, pitting rust which is a bit more serious and can leave small holes in the metal surface and flaky rust – the most common type of surface rust – which will need to be taken care of with sandpaper or a wire brush.
Scale rust is the next level up. This type of rust appears when surface rust is left untreated for too long and starts to corrode the metal on body panels.
Finally, you’ll be dealing with the big bad wolf of rust: penetrating rust. This advanced and destructive type of rust can wreak havoc on your campervan. For example, rust causes a water-tight seams to fail, exposing more areas that were not previously exposed, you could end up needing to replace entire parts and body panels… which, yes, is expensive.
Accelerators of rust
You might think you’re taking good care of your vehicle, but some factors outside of your control can accelerate the corrosion process. Many of these accelerators are linked to your geographic location, so if you think the place you want to keep your campervan, or travel in it, might cross some of these locations, take extra care with your rust checks and treatment.
Poor weather conditions: Unfortunately, no place on earth stays rain-free for long. Leaving your campervan outside in heavy rain or regularly driving through puddles increases the chances of rust developing. Water tends to gather in certain areas, like the rear tires, wheel wells, and wings, which can become particularly prone to rusting if not dried properly. In a camper we also need to take particular care with insulation, as water can get into the internal walls of the campervan. More on that in our guide to insulation.
Nice weather (hot and humid): air can also attack any exposed metal on your campervan. A never ending sauna for your campervan.
Rural locations: If your campervan is left somewhere particularly rural and very open to the elements, you will likely have a bigger problem with rust than those in urban and sheltered areas. You can thank things like potholes and the likelihood to pick up tiny nicks when driving down backroads.
Coastal living: The chemical reaction that causes rust involves electrons moving around, and they do so more easily in salt water. It’s like giving rust steroids. Where do we find Salt Water? On the coast. Salty sea water has a knack of travelling in the wind and finding its way to even the tiniest patches of unprotected pieces of metal, causing an campervan – already prone to rusting in average conditions – to deteriorate considerably quicker.
Where to find rust
Rust can occur anywhere on your campervan, but there are certain areas where it tends to develop more frequently.
One common spot for rust is around the wheel arches, where dirt, salt, and other debris can accumulate and provide a favourable environment for rust. Don’t miss cleaning up inside your arches when cleaning the van.
Rust can also appear on the underside of your campervan, which is exposed to road salt and water almost non-stop. You can use a pokey stick to get up in and underneath places like the wheel arches, and flooring. Pray for a scratching feel, because if you feel a crunch or softness, you might have some work to do.
Sills and Seals: the door sills, window sills, and the area around the base of the windshield and rear window are additional areas where rust is known to occur.
The roof of your van is especially susceptible to rust due to its exposure to the elements. Checking the roof for rust spots is a smart practice to adopt. Rust, particularly around vents (where water can collect and pool) can corrode through the thin roof quickly and from there on is inside.
Lastly, rust spots may appear on the very front of the van, the panel above the windscreen, or lower side panels where little stones kick up or where bushes scrape against the side of the van.
Fixing surface rust on a campervan
If you leave rust untreated, it will continue to gnaw away at the metal, making it more vulnerable to more serious damage. Left untreated, rust can spread to other areas of your campervan, leading to an even more expensive problem to fix in the long run. Better to nip in the bud then, yeah?
If you catch rust early, you can often remove it yourself using a rust remover or sandpaper. Yes, you read that right. You don’t need to be a professional mechanic to tackle this issue. Of course, if the rust has already penetrated deep into the metal, you may need to replace the affected parts, but catching it early will save you a lot of time, money, and headache.
Here’s how:
- Sand Down the Rust
Sanding down rust fact is a tedious and time-consuming task, but a necessary evil if you want to rid your campervan of rust. Using a drill with a wire brush head is a quicker and more efficient way to remove rust than sandpaper, however, if you’re feeling nervous (understandably) starting off with some sandpaper is also an option. Just be prepared to exercise shoulders, grip and patience. Once you’ve removed the rust, run over with brush or hoover away the debris and wipe the surface with white spirit.
(If the rust has eaten through the metal, you’ll need to use a grinder to grind down all the rust until you reach bare metal. This step may seem counterintuitive, but it’s necessary to fix the problem properly.)
If you have some rust in an extremely hard to reach area, consider using a rust converter. Apply the converter, and it will react with any remaining rust, converting it into a stable compound and stopping it from spreading. We wouldn’t recommend this on body panels. And remember to use protection, this is chemistry.
- Apply Rust Remover
After sanding or grinding, apply Rust Remover to a microfiber cloth and wipe the metal with it. Make sure to wear gloves, a mask, and protective glasses while applying it since it’s a flammable vapour and horrible liquid that can damage your eyes and burn your skin. The time it takes to remove rust using rust remover depends on the severity of the rust on your van. Light rust takes around 30 minutes to remove, while heavy rust can take up to 24 hours.
- Repair the Holes
If you have a hole in the place where the rust was, you’ll need to fill it using a metal epoxy putty. Mould it in your hands till it’s warmed up, then apply it on the inside and underside of the campervan. Don’t forget to keep on your gloves and a mask to protect your skin from the toxic epoxy.
After 24 hours or so, the epoxy will harden or become rigid. When this happens, sand down the excess putty to smooth out the surface.
- Prime
Now that the rust is out, you have your canvas, but before we start to paint, we have to make it blank. To do that, you add a primer (paint) to the metal surface. A primer will protect the metal against rust and provide a good base for the topcoat of paint. There are some primers that bonds to any remaining traces of rust and transforms it into a non-rusting, paintable surface. Rust-Oleum, Rust Reformer and Red Oxide primer are popular choices
- Paint
It’s time for the final step – applying metal paint. Hammerite white metal paint is an excellent option for a smooth finish that protects metal from weather elements (especially if you have a white van!)When painting, remember to paint both the top and underside of the epoxy. You might need two coats, leaving it to fully dry for 24 hours in between. And if you live in a country where the weather is unpredictable, like England, wait a few extra days for the paint to fully dry.
Don’t forget to apply a generous amount of treatment around any metal seams, especially around the bottom of the wheel arch box, where water often gets trapped. And voila, your campervan is now rust-free and looking as good as new!
Tools and supplies needed
- Power Drill (800W) – for driving and drilling
- Wire Brush or Wire Brush Drill Bits – for physically removing the rust
- Selection of Sandpaper – for sanding down the metal surface
- Rust Converter or Rustins Rust Remover – for dissolving rust
- Red Oxide Primer – for priming the metal surface before painting
- Hammerite Metal Paint – for protecting bare metal from rust
- Metal Epoxy Putty – for repairing holes in your van
- Paint Brush – for applying paint and primer
- White Spirit – for cleaning surfaces
- Dustpan and Brush or Hoover – for cleaning up debris
- Safety Glasses – for eye protection
Some additional things to know about rust:
One of the most common areas for rust to start is from the edges of the metal panels. These areas are more prone to abrasion and knocks, causing the paint to chip and exposing the metal to the elements.
Rust tends to creep and, once metal is exposed, can quickly spread under the paint, lifting it as it goes and exposing more metal to rust. 65% relative humidity is sufficient for the rusting process to begin, indicating that direct water contact is not always necessary.
Consider using a seam sealer or flexible sealant around the seams and corners of body panels. This can help prevent the paint from cracking and exposing the metal underneath.
It is crucial not to ignore even a small rust spot because it’s likely that more rust is lurking beneath the surface. When rust comes through the paintwork, it’s usually because the rust has penetrated the full panel from the other side, which means you are going to have to do something about it.
Rust converter and rust remover are two different products that can help remove rust. Rust converters neutralise the rust reaction and form a latex layer over the top, while rust remover dissolves the rust and removes it, as long as it hasn’t fully penetrated the panel.
Complete removal of rust is ideal to prevent further damage, but it may not always be possible. Regular inspection and treatment with rust converter and paint are recommended.
Proper preparation is just as important as the paint itself, which includes removing rust, washing the area down with detergent, and removing all dust, grit, grease, and dirt.
Even the smallest bit of grit, dirt, or grease can cause paint failure, leading to rust. It can also cause water-tight seams to fail, exposing more areas that were not previously exposed.
Rust traps water, especially in small pits, which can eventually cause flaking and lead to even more water being trapped between the rusty flakes. So, keep these tips in mind to prevent rust from taking over your trusty campervan.
Under-sealing the whole van isn’t as expensive as you might think (~£150), and might be a worthwhile expense if you are spending time in any of the ‘danger’ rust zones, as discussed up the page. It will give a heavy-duty protection for the underside of your campervan and other high-impact areas that are exposed to various things like stones, water, and corrosion.
What we did
We have a crafter, based on a sprinter, renowned for rust. A good trick is to buy a van with very little rust on it, which helps a lot.
Fortunately, our van came undersealed, so we didn’t need to worry about any penetrative rust.
For that reason, we didn’t strip under the floor.
We do have some small bits of surface rust appearing on the van though.
We’re going to wait until we’ve travelled and saved up a bit, before attacking them. Si has a plan to re-spray the van at some point.