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How To Remove Powder Coating (4 Different Methods)

December 05, 2018

How To Remove Powder Coating (4 Different Methods)

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If you’ve ever tried to strip an object that has been powder coated before, you know how stubborn it can be. Durability is a major benefit of powder coating but also makes it a pain to remove.

How can you remove powder coating? Powder coating can be removed using chemical strippers, heat, abrasives, or lasers. Each method has its advantages and disadvantages that you’ll need to consider when choosing which to use.

In this article, we’ll discuss the main methods that you can use to remove powder coating. As well as the pros and cons for each, safety precautions you should take, and what supplies you’ll need for each method.

How To Remove Powder Coating

Powder coating uses an electrostatic charge to cover every inch of an object. It’s so effective that it can be hard to remove.

There are four main ways to remove powder coating, which will be covered in-depth in this article:

  • Chemical strippers
  • Heat or thermal removal
  • Abrasive blasting
  • Laser removal

Why Would You Need To Remove Powder Coating?

Fixing mistakes. If you’ve just started powder coating yourself, you’re bound to make errors. On your first few tries, your coating might not come out as good as you’d hope for. So you’ll want to be able to remove the powder coating to try again.

Refinishing. If you have an old piece of metal, you might just want to refinish or update it to keep it looking shiny and new.

Cleaning. After you’re done powder coating, you’ll need to strip your cleaning hangers and racks or they will just keep building up with thicker and thicker coats each time you complete another job.

Method One – Chemical Strippers

When it comes to removing powder stripping, your first option is to use a chemical stripper.

This option is great for DIYers who are just doing projects in their backyard and might not have the equipment needed for some of the other stripping methods.

It’s great if you’re only needing to strip powder coating a couple of times per year.

There is a whole range of chemical strippers available from home improvement retailers like Home Hardware and Lowes. There are many different types of chemicals to choose from which have various applications, so it’s important to choose a stripping product that meets your specific needs.

Paint stripper (sometimes called aircraft stripper) is one example of a chemical stripper. It has a pretty wide range of applications and is suitable for use at home, so it can be a great place to start. Although more stubborn powder coating might not come off with a basic paint stripper.

Oven cleaner is another chemical that can strip some types of powder coating and is cheap and easy to get.

You can get chemical strippers in one-time use aerosol cans or gels. They usually will need to be applied multiple times to get the job done. Look for products that contain the chemical methylene chloride to be sure it will be capable of removing powder coating.

Be especially careful with what products you use on powder coated aluminum. Some chemicals like caustic soda are very effective at cleaning steel and iron but will destroy aluminum.

Chemical Stripper Pros

Using chemicals to remove powder coating will leave you with a uniform surface after you’ve removed the coating. Some other methods like sandblasting can scratch or remove tiny pieces of metal. If you’re not re-coating the surface you’ll probably want it to be smooth and shiny without scratches.

Chemical strippers are cheap and available in small quantities. They’re great for a one-time job or for someone who doesn’t need to remove powder coating very often.

Chemical Stripper Cons

Chemicals used to remove powder coating can be really bad for the environment and have strict requirements on how to dispose of them. They’re also more dangerous to work with compared to other removal options.

Chemical strippers also don’t leave a profile for a new coating of paint to stick to. If you’re planning to re-coat the metal you’re stripping, you might want to sandblast it instead. The scratches and marks from the adhesive make it easier for many types of paint to stick to metal.

How To Work With A Chemical Stripper Safety

Working with chemicals that are capable of melting powder coating off metal can be dangerous. Even a small drop will burn your skin, and getting it in your eyes can cause permanent damage.

Take the safety warnings seriously and wear the proper equipment.

You’ll want to wear thick rubber gloves, ideally elbow-length. It’s best to get a cheap pair and immediately throw them away when you’re done, rather than trying to clean them. Otherwise, you risk getting the chemical on your skin after you’ve taken your gloves off.

Eye protection like goggles is also a must.

A heavy-duty apron will help protect you in case of any spills or splashes. Wearing long sleeves is a good idea too.

Finally, proper ventilation is required too. Many strippers contain dangerous chemicals that could cause cancer or make you pass out if you’re breathing them in a closed room. You might want to wear a full-face respirator when handling these chemicals if you’ve got one.

Make sure to keep any small kids or animals out of your workspace while you’re using chemical strippers as well.

You might need to use a chip brush to help scrape the powder coating off your object once you’ve applied a chemical stripper. Be careful not to fling stripper around when doing this.

Using A Chemical Stripper – Steps To Follow

1. Do a spot test first

You’ll want to start off by spot testing your item with your stripper to make sure it will work. Apply a small amount of the stripper by following the recommended instructions. Then try to scrape off the powder coat with a scraper.

If the coating comes off fairly easily, you can go ahead and apply the stripper to the entire object. If the coating is still really stuck on, you can spot test another area and give it more time. Or you might need to get a stronger product if it still doesn’t work.

2. Apply your stripper

Coat the entire part in the chemical stripper. Let it sit for the same amount of time that you used for your successful spot test.

3. Scrape the coating off

After enough time has elapsed, it’s time to clean the powder coating and solvent off. You can use a bladed paint scraper or a chipping brush for this step to start with.

Once most of the coating has come off, you can go over the metal again with steel wool or an abrasive pad to get any remaining coating off.

If you’re struggling to get all of the coating off, you might need to re-apply the chemical stripper and wait again.

4. Wash your part

Rinse your stripped part off with water and detergent to remove all remaining traces of coating and chemicals. Make sure to dispose of the removed coating carefully.

Stronger Chemical Strippers For Larger Jobs

Most of what I discussed above regarding chemical strippers is aimed more at DIYers and hobbyists.

If you need to strip powder coating off large numbers of pieces or you just want to do it faster and more efficiently, I’d recommend a stripper that’s designed for more industrial applications such as Benco B-17 or 1010P.

Benco B-17 Industrial Liquid Stripper

Can strip about 3mm of powder coating in less than 20 minutes. It contains stronger and faster-acting chemicals like methanol chloride, phenol, and hydrofluoric acid that aren’t found in retail strippers.

1010P is less powerful than B-17, but will still work better than anything you can buy at your local hardware store.

Be aware that these industrial chemicals can normally only be ordered in larger quantities – such as 5 gallons, 30 gallons or 55-gallon drums. So they’re really only a good solution if you own a shop and will be stripping powder coating on a regular basis.

You will also need a container to do your stripping in unless you intend to strip items in the drum it was shipped in.

You’ll need to be extra safe when handling industrial strength chemical strippers. They can remove powder coating faster than retail strippers, but that means they can do real damage to your skin if not handled correctly too.

Benco B-17 stripper costs about $200 for 5 gallons. Although many companies will no longer ship it to residential addresses since it’s considered a hazardous product.

Method Two – Heat or Thermal Removal

Removing powder coating using heat is safer and less risky than using chemicals. They break down the powder coating into ash that can be easily washed off.

There are a few different methods you can use: a bake off, burn off, thermochemical, or fluidized bed system. Each one uses different temperatures. Generally, the higher the oven temperature, the faster the coating will come off.

Thermal removal methods aren’t really practical for small shops or DIYers since you need specialized ovens.

Bake off. This method uses temperatures of 650 – 750 degrees Fahrenheit and will take about 3 to 6 hours to clean off powder coating. After baking, you need to wash the powder coating off so that it doesn’t re-stick to the metal surface.

Burn off. This method uses temperatures of 1000 – 1200 degrees Fahrenheit. All powder coating gets removed in just a matter of minutes at such high temperatures. It’s hard to do this at home, and it’s usually only used in production facilities that need to remove large quantities of powder coating.

Fluidized bed system. This method uses something abrasive like sand that has been heated up to around 800 degrees Fahrenheit which is rubbed against the product to strip the powder coating off. It’s kind of a mix between a thermal and abrasive method.

Thermochemical. Uses a mixture of chemicals and high temperatures to strip coating. Usually done at temperatures of 800-900 degrees Fahrenheit.

No matter which thermal method you use for removing powder coating, it’s important to make sure that hangers and racks used can resist the high temperatures used. For example, soldered joints or parts made of magnesium won’t work since temperatures can reach 1,000F or higher.

All of these methods create byproducts called VOCs or volatile organic compounds. These need a special exhaust system with afterburners to destroy.

Heat Removal Pros

Using a heat system is fast and efficient. It’s great for doing large volumes of stripping.

When done correctly, thermal processes release nearly no contaminants back into the environment, unlike chemical strippers.

Heat Removal Cons

The equipment used for thermal stripping consume a lot of energy and can be expensive to buy. They can easily cost thousands of dollars.

Some heat removal methods need a wash phase to remove burnt powder after they’ve been processed.

Whether you use electricity or natural to power your ovens, they will result in a high utility bill.

The high temperatures used mean you risk altering the shape of the underlying metal. Heat removal also doesn’t leave a profile for new paint to adhere to, similar to chemical stripping.

Method Three – Abrasive Blasting

Abrasive blasting (sometimes called mechanical removal) uses an abrasive media like sand which gets shot at the powder coating surface at high speeds. This strips the coating off the metal’s surface.

To use this method, you’ll need a sandblast cabinet. Sandblast cabinets come in two main types, pressure and suction. For removing powder coating it’s best to use a pressure sandblast cabinet. It’s better at removing the stubborn powder coating.

If your object is too large to fit in a sandblast cabinet, you’ll need to set up a sandblast room or tent.

You can’t simply use abrasive blasting in your garage. The abrasive media will go flying beyond the object you’re stripping and damage anything else in its path.

Abrasive Mediums

Depending on how thick your layer of powder coating is, you’ll want to consider different abrasives. Lighter abrasives like glass bead work if the coating is light. But for thicker coatings, you’ll want something more aggressive like steel grit or aluminum oxide.

Other abrasives include:

  • Sand
  • Water
  • CO2 pellets
  • Garnet
  • Dry ice
  • Slag
  • Plastic Media

Picking the right media affects the profile left on the metal’s surface, as well as how fast it works. The more aggressive a media you choose, the faster it will clean but it will also leave the roughest surface on the metal.

Abrasive Blasting Pros

Using abrasives is fairly cheap if you’re doing it on any kind of scale. The equipment is much less expensive than using ovens. It can be good for smaller shops between what a DIYer needs and what a large-scale industrial operation would use.

Abrasives are also a portable option. You can use a small sandblasting cabinet or pot to remove powder coating in the field.

Using abrasives leaves a surface profile, which makes it easier to apply some paints and coatings.

Abrasive Blasting Cons

Abrasives can be a bit slower of a stripping method. It usually takes about 30 seconds for each square inch of powder coating that you want to strip away.

Each part you want to strip has to be blasted individually, which means higher labor costs.

Parts that have irregular shapes can be difficult to blast and can trap abrasives, potentially causing problems with future coatings if not fully removed.

Abrasives are good for steel and harder metals, but they can erode softer metals like aluminum.

Method Four – Laser Removal

Big scientific advancements have been made when it comes to removing powder coating. Now you can even do it with specially-designed lasers!

Lasers work by burning powder coating off of metal, similar to the use of ovens, but in a significantly more directed and focused way.

Laser Removal Pros

Lasers are very precise and can strip powder from a small area, but they can be used for large surfaces too.

They can be used on nearly any material since they don’t alter the substrate underneath the powder coating. The heat of the laser doesn’t touch the actual surface of the metal while stripping, which makes it perfect for aluminum.

Lasers have little to no impact on the environment.

Laser Removal Cons

As you’d imagine, lasers are pretty cutting-edge technology and they can be very costly to buy. For that reason, lasers are only really practical for stripping in a production environment.

Like all of the other methods except abrasives, laser removal doesn’t leave a profile on the metal’s surface, meaning extra steps might be needed before re-applying paint or another powder coating.

Summary: Which Powder Coating Removal Method Should You Use?

Which method you use will depend on the quantity of removal you need to do, your substrate, and the results you want. Here are some recommendations based on different needs though:

For the lowest cost. If you’re only stripping once or twice per year, picking up a can of a chemical stripper from your local hardware store is probably the cheapest option. For more regular powder coating removal, abrasive blasting is cheapest.

For the fastest removal. If you need a part cleaned quickly, a burn-off system is the way to go.

To minimize environmental impact. Lasers are the most environmentally-friendly stripping method, followed closely by thermal stripping. Avoid chemicals if there are environmental concerns.

For dirty or greasy parts. If you’re dealing with parts from engines or other equipment that comes in contact with oil and grease, thermal stripping is best. It will burn away all of the impurities along with the powder coating.

For steel parts. Abrasives work quite well on steel since it’s strong enough to

For delicate parts. Lasers are best if your item can’t withstand high heat. Chemical stripping is a more affordable option if you only need to clean a few pieces of aluminum.

For wheels and rims. Normally a combination of sandblasting and chemical stripping is used when you need to remove powder coating from rims and wheels.

Conclusion

Removing powder coating yourself can be a lot of work.

To figure out what method you’ll use to remove powder coating, you should consider a few things like the volume of powder coating removal you need to do, as well as the type of metal you’ll be stripping.

If you only need to remove powder coating once or twice a year, it’s probably easiest to just buy some commercially available chemical stripper.

For small shops or a hobbyist who frequently needs to remove powder coating, using abrasives with a sandblast cabinet can be a good solution.

Bake off ovens, blast rooms, and large chemical stripping tanks make sense only on larger (industrial) scales for large batches of work.

Deciding the right method for removing powder coating normally involves balancing out the time it will take you compared to the cost investment required.

Have you ever removed powder coating before? Which method did you use? Let us know in the comments section below!

Dustin Yarc

Dustin Yarc writes about technology, personal finance, and many other topics. If you’d like to learn more about him, you can visit his website. - www.dustinyarc.com

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