Project LuLu: Rust Bucket

Old cars get rust. That’s pretty standard across the board and thankfully, LuLu only has cosmetic rust. I still have to make sure it doesn’t spread, and eventually I want to get her a paint job, so my first big project is fixing her rust.

For the most part, there is really only one spot of rust. The drivers side panel on the back of the van has rust on the inside and on the outside. To prevent additional work later, I wanted to start here.

This project was kind of scary but also exciting. I’ve never done absolutely anything with rust before. It definitely took a lot of guts for me to be confident enough to take a sander to my vehicle. Check out our video here to see the process in action. It’s part one, so check out LuLu’s YouTube channel for the rest of the videos. Make sure to subscribe so you don’t miss out on any of the action (especially once we hit the road!).

Parts Needed

Items needed for this project are:

1. Orbital or belt sander (I used an orbital sander)
2. Block sander
3. 50 grit sandpaper (for orbital sander and block sander)
4. Various other grits (such as 80 to 200) of sandpaper (for orbital sander and block sander)
5. Degreaser or other cleaning solution
6. Rust converter
7. Bondo body filler
8. Metal patch
9. Small paint brush
10. Putty knife/spreader (the silicon spreader worked great because of the flexibility)
11. Safety eyewear
12. Respirator or dust mask
13. Gloves
14. Krylon 2x Coating Gloss Enamel Spray Paint (I used 2 cans and would’ve used part of a 3rd)
15. Frog Tape (or other painter’s tape)
16. Newspaper

First off, I bought the wrong sandpaper for my orbital sander. I haven’t used it recently and I forgot I needed the velcro kind. I bought the adhesive sandpaper because that’s what they had at the parts store. That meant a second trip. Combined, this list took me a total of 4 trips to 4 different parts stores. Word from the wise: any brand of rust converter should probably work as should any body filler. Check in with the staff of course, but I really didn’t need to go to Napa specifically to find the Napa brand rust converter (that they didn’t have in stock anyway).

Step 1 – Sanding

Very important: wear your safety gear!!! You don’t want to breathe in rust and metal and paint and you don’t want those particles in your eyes either!

The first thing that I did after putting on my safety gear was immediately take my orbital sander to the rusted panel. I probably should have cleaned the area first, but I’m not sure how much that matters. I sanded then cleaned then sanded, then cleaned again. The goal is to get rid of as much rust, paint, and dirt as possible. You want to get to bare metal if you can. I did not use a grinder at any point as I read that it can cause unwanted grooves and pitting if you aren’t very careful. That is an option, though, particularly for heavily rusted areas. For my cleaner, I had Goo Gone lying around. I used that and an old t-shirt to remove dirt and rust stains from the panel I was working on. This really helped me see exactly what was rust and what wasn’t so that I wasn’t wasting my time. After a couple rounds of this, I took the block sander to some parts that were difficult to get to with the orbital sander.

Step 2 – Rust Converter or Remover

Once sanded and cleaned, you can then apply your rust converter. For this part, you want to pour out a small amount into a bowl. You don’t want to accidentally convert your entire bottle because its contaminated with rust. You also can’t add excess back into the bottle, so use a little at a time. I used about a 1″ brush for this but you can decide what size brush based on the area of rust you’re working with. It can stain your paint so it is recommended to avoid applying it to painted areas that you aren’t wanting to paint over. Once you apply it, you’ll see it start to change colors. It will typically change to purple first, then black. This means its working. Follow the instructions on the bottle, but you should be able to add an additional layer if needed and it will also list the cure time.

Keep in mind, this is converter not remover. Rust remover can be used on surface level rust that is covering unrusted metal. Rust converter changes rust from iron oxide to iron tannate. Iron tannate is stable and won’t continue to eat way your metal like iron oxide will.

Step 3 – Body Filler

Once your converter has cured, you can now go over your rust with Bondo. Bondo (and i imagine other body fillers) is a two part product. The filler, which has almost like a runny clay appearance, and the cream hardener, which comes in a small tube. These get mixed together to form a uniform filler. Without the hardener, the filler won’t set. You’ll combine these per the instructions on your filler. Make sure to only make very small batches of this because as soon as it starts to harden, it becomes impossible to work with. I learned this the hard way. When working on the very last panel, I added too much hardener to the filler and it got hard in my mixing bowl in just maybe 15 seconds of not using it. You want to make sure its smooth and uniform in color when mixing.

Once mixed, you are going to take a small amount of this (in relation to your project size) and smooth it with a putty knife, or something similar, over the rusted area. I used the Bondo putty knife and I really liked it. Its a pliable plastic so you can remove the bondo from it pretty easily. Any plastic spreader should work fine. To prevent cracking or the need to sand excessively, its recommended to keep the final thickness of the Bondo to 1/4″ or less.

If you are working with holes of almost any size you will need to use some kind of patch or support framework for the bondo to stick to. I used an aluminum self-adhesive patch. It was very easy to work with and you can cut it to the appropriate shape using household scissors. The hole I had was along a corner, so I folded the patch to a 90 degree angle, stuck it on, and put the bondo right over it. It worked like a charm! There are also options such as fiberglass patches that are larger. I believe these require a hardener, but I’m not very familiar with this method.

Step 4 – Sanding (again)

The final step(s) before painting is sanding, smoothing, and feathering your Bondo. Ideally, you want the filler to blend in seamlessly with the body of your vehicle so that you can’t see the rusted area once you paint. To do this, you are going to want to start with a coarser grit and work your way towards a very fine grit, shaping as you need. You’ll want to do this over time (see the Bondo instructions) because the ability to sand the filler changes as it hardens. Luckily for my beginner abilities, my panel is basically flat so I didn’t have to worry about too much shaping. I will say that an electric sander of some kind makes a world of difference. I could’ve done much more sanding, but because this area won’t be seen (and is primarily just for practice for me), I decided to save myself a little work and not worry about it too much.

And that’s it! Now you should be ready to paint.

Step 5 – Paint

I wasn’t originally going to paint this panel, but along the way I decided to feel fully finished, I wanted to paint it. Using Frog brand painters tape to tape the areas I didn’t want paint on, I decided to use a high gloss white spray paint over the rusted area on the inside. The trick with spray paint is to use long, even strokes. Always start and stop before/after the surface you’re painting to prevent runs. Also make sure you’re working in a well-ventilated area. I was not and it was out of my control, so I took frequent breaks.

I think it looks really good considering this is the first time I’ve ever done a project like this! I have one more interior piece of rust to work on before I begin on the outside. On the outside, I think I will wait until I get her professionally painted.

Stay up to date on her build by visiting the DIY section here on A Bus Named LuLu. Safe sanding!