Introduction: Removing Powder Coating From Aluminum

Powder coating can be removed from steel parts by sandblasting. A local powdercoater recommended JASCO paint and epoxy remover after saying they had two sandblasters, one wouldn't touch the coating, and the other was so big it might destroy this aluminum intake manifold.

You should find JASCO strippers in almost every hardware store in the USA. First I bought an orange stripper that was more environmentally sensitive, but it barely even touched to the coating. The JASCO works after multiple coats, scraping the coating with plastic brushes, then scrubbing with brass brushes and carb cleaner. You can be more aggressive and use metal paint scrapers and heavy wire brushes, but I wanted to keep the original texture of the manifold as much as possible.

Other methods to strip powdercoating from aluminum might be to leave it in industrial strength carb cleaner over night, or find a shop that can strip it in a similar bath. Sandblasting might work just fine, but could require using a different blast media, I don't know. Any input on other methods would be great.

Safety:
The stripper is very nasty stuff. You'll feel even the smallest drop because it will burn your skin. Getting it in your eyes will probably cause irreversible damage. Do not ignore the safety warnings. Only use thick disposable gloves, wear eye protection, long sleeves are a good idea, and proper ventilation is a must because huffing the stuff probably gives you cancer.

  • Wear Thick Disposable Rubber Gloves (buy a box and throw them away every time you take them off)
  • Use Eye Protection (lab goggles)
  • Wear a Long Sleeved Shirt
  • Have Adequate Ventilation

Supplies:
  • JASCO Premium Paint & Epoxy Remover (1 quart)
  • Chip Brush (1)
  • Plastic Paint Scrapers (1 narrow, 1 wide)
  • Carb Cleaner (1 can)
  • Brass Bristle Brushes (5 total)
  • Paper Towels / Rags (many)

Step 1: Apply the First Coat of Stripper

The first stripper I tried was called Citristrip. It smells like oranges and is less toxic, but it was barely removing anything from the powder coating. I did find it useful to use after the majority of the coating was stripped, because it was safe to apply it in the morning and strip it after work.

JASCO works a lot better, but this whole process is still incredibly time consuming.

Apply the Stripper with a Chip Brush:
Brush the stripper on smoothly! The bristles can fling stripper around if you're not careful, and you'll know when this happens because your skin will burn. I really recommend wearing the lab goggles when applying it for the first few coats, just to be safe.

  • Pour some of the stripper into a metal container. I cut the top off of an aluminum can and it worked fine.
  • Begin painting it on liberally. After 15 minutes, come back and slop on another thick coat.

Continue applying coats, keeping the piece damp with stripper (don't let it dry out in a breezy environment, but make sure you have proper ventilation). The powder coating will start to bubble up and then you can scrape it off. Some recommended not scraping at all, just applying coat after coat until it falls off, but I found it went a bit more quickly if you scrape away what you can with the plastic paint scraper in between coats. The stripper will work it's way underneath the powder coating in any places that are chipped up or scratched, so you'll see progress in those areas first.

  • After 3-4+ coats and stripping, you should start seeing bare metal.
Flat surfaces will be easy, but tight places will take more time. Having a narrow scraper will help. Over time, the scraper will get worn down. Wipe it off and take it to the belt sander to give it an edge again.

Step 2: Continue Applyling Stripper

Continue applying stripper:
  • Keep applying stripper to the spots that need it until you get to a point that the only residue left is trapped in the texture of the aluminum.
  • When the majority of the powder coating is gone, use the stripper with a bristle brush in the tight places.
This is about the half way point, removing the rest is easy but tedious.

Step 3: Scrub With Carb Cleaner and a Wire Brush

Carb Cleaner or Brake Cleaner and a brass bristle brush and hours of time was enough to remove the rest of the residue. Acetone seemed to work too, but I had better results with the carb cleaner.

Clean the residue trapped in the texture with Carb Cleaner and a Wire Brush:
If you're going to repaint or refinish the part, buy wire brushes that aren't brass. If you want to keep the texture and not change the finish that's there, using anything harder than brass will scratch the aluminum. I didn't see any new scratches with the brass brushes.

  • Spray the part with carb cleaner
  • Scrub in a circular motion with the wire brush, and immediately wipe the residue off with a towel. If you don't wipe off the residue, you'll just be moving it around, and it's hard to see where to work.
  • Repeat those steps and you should get pretty good results.

At some point you won't need to use carb cleaner anymore, just the wire brush will do the job.

Step 4: Back to Raw Aluminum

After hours and hours of stripping, I just wanted to get the manifold installed. A few more hours would have finished it up.

Hope this helps anyone trying to strip powder coating off aluminum, it's pretty tough stuff.