Rust-Oleum Automotive Filler Primer Custom Spray 5-in-1, Gray

This stuff is great! Way better than expected. Will definitely buy again

Good quality primer.

I used this Rust-Oleum Automotive Filler Primer on a car project about 7 years ago, and it performed really well. I picked up another can because I have to touch up the paint where someone hit the car. Overall, this is a very effective automotive primer that performs as expected and can make a big difference in paint prep work. It’s a solid and reliable choice for DIY automotive paint jobs (At $12.82 at the time of this review). The key to getting great results with this product is proper surface prep, but once that’s done, this primer really shines. It lays down evenly and does a good job of filling in small imperfections, which can save a lot of time compared to trying to get every surface perfectly smooth with body filler alone. One of the standout features is how well it sands. After it cures, it can be wet sanded to a very smooth finish, and it doesn’t crumble or remain soft. The “filler” characteristic is noticeable—it creates a solid, slightly thicker coat that helps level out minor surface defects and scratches. Once sanded, it provides a great base for topcoat paint, helping achieve a more professional-looking finish. It also holds up well once fully cured and doesn’t feel brittle or weak.

Got this to cover some bondo and sand some high spots and it worked great. Went down smooth and sprayed nice. Covered everything really well and once it cured it sanded buttery smooth. Best primer I've used for this.

Used to prep and prime 3D prints. Did a fantastic job smoothing everything out before paint. Just felt like I didn’t get as much mileage out of this can as I did with the standard nozzles despite using the different nozzles appropriately.

I've recent gotten into painting 3D printed parts, and the consensus online was to use rust-oleum automotive filler and primer. I've used Rust-Oleum automotive filler and primer to prime and smooth the prints. I gave it a go once before with a standard spray nozzle, and it worked well, but the coverage was too broad. When I saw this new adjustable nozzle was available on new bottles, I was excited to try it. The product comes in a standard well labeled spray can. Rather than a traditional cap, you have the new nozzle. It comes locked, and you rotate it to different settings (high output, standard output, low output, vertical fan, horizontal fan). Instructions tell you to set the nozzle, shake the can, spray in a back and forth motion over a target at about 12" away, and apply 2 (or more) coats a few minutes apart. It dries to the touch in about 10 minutes (ready to wet sand), and in a few hours (depending on the coat), you can dry sand. Overall, I was pleasantly surprised to find the nozzles really help in controlling coverage, and the product does a great job covering layer lines and the remains of support scars. It bonds well to PLA and PETG, and the color makes it easy to see imperfections that need to be sanded. At $15, it's about twice the price of the standard nozzle at my local hardware store, but the improvement in control results in better performance and minimized waste, and I'll be buying it again for smaller objects.

If you’re putting this on an automobile you’re setting yourself up for doing it again within a few years (even with the base coat and clear coat). There’s nothing “automobile” about it. The sun will cook the life out of it and the rain will finish it off.

I’ve found this Rust-Oleum Automotive Filler Primer to be pretty handy when it comes to prepping paint. It does a good job of filling in small imperfections and building up layers smoothly. The spray nozzle works well and makes application pretty easy. On the downside, I do feel like the price is a bit high for just one can, but it tends to do the job well when I need it.