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How to Use a Pressure Washer to Remove Rust

How to Use a Pressure Washer to Remove Rust

Metal things look nice when they look new and shiny. However, over time, oxidation will take over and your metal objects around the house will start to corrode. Whether it be small common household items or large appliances, the presence of rust is simply an eyesore.

There are many ways you can remove rust from metal objects. Have you considered using a pressure washer to remove rust? It’s quite simple and quick, and can save you a lot of time if it’s used on things with large surfaces areas, like your house siding and concrete walkways. To remove rust using a pressure washer, spray the item with at least a 2000 psi washer. Then let it dry before coating with a protective sealant.

Let’s take a closer look at the steps involved, including some optional prep work and safety measures to keep in mind, and priming with rust-inhibiting paint.

Prepare Rusted Item/Area For Pressure Washing

Prepare Rusted Item/Area For Pressure Washing

A pressure washer can become a dangerous tool if not used properly. The water pressure discharged is strong and can cause serious damage and bodily harm. Pressure wash in an open area and keep kids and pets a safe distance away.

Use Safety Coverings When Pressure Washing

Use Safety Coverings When Pressure Washing

Safety should always be a concern when operating a pressure washer. Wearing protective coverings might come across as excessive, but it should be done. 

Safety goggles

Safety goggles need to be worn at the very least. Water that is projected out will ricochet off whatever surface you’re cleaning and might possibly hit you with high velocity. I would say your eyes need a little bit more protection than other parts of your body.

Earplugs

Gas powered pressure washers have strong and loud engines. If you have sensitive ears, use earplugs or other forms of ear coverings.

Dust mask

Consider a dust mask or respirator. Pressure washing a rusted item might break off chips of rust or paint, which could be hazardous to your health. You don’t want to be breathing those stuff in. 

Waterproof gloves

When you’re working with water things can get slippery. Throw in the use of water pressure, which can be unpredictable, and you’ve got a recipe for disaster. Waterproof gloves and provide some measure of stability and grip while you operate a pressure washer.

Steel toe boots

It’s common practice to pressure wash things by aiming the wand at a downward angle. Your legs and feet might become exposed to the water blast if you’re not careful. Steel toe boots will provide some protection against injury to your feet.

Set Up Your Washer and Choose Your Nozzle

Set Up Your Washer and Choose Your Nozzle

There’s a couple of things you should be mindful of as you get ready the equipment you’ll be using to pressure wash your rusted surface. Choose the right kind of washer to clean with and the appropriate nozzle to use.

Washer

Rust can be difficult to get out. I’d recommend a medium or heavy-duty pressure washer for this particular cleaning project. This probably means a high-end electric or a gas powered pressure washer.

A light-duty pressure washer uses less than 2000 psi, which I think is insufficient to remove rust and paint. A medium-duty washer has a psi range between 2,000 and 2,800. A heavy-duty unit has a psi range between 2,900 and 3,300.

PSI is a metric used to measure the force of the water pressure that is discharged. It’s short for pounds per square inch.

Nozzles

There are a handful of nozzles you can choose from. You’ll want to choose one that has a small orifice size, so that it produces a focused spray pattern and discharges a high-velocity water stream.

For large and durable surfaces, such as a driveway, go with a yellow tip (15 degrees) nozzle. If you have something that’s been giving you significant trouble with rust removal, give the red tip (0 degree) nozzle a try. The red nozzle will probably be the most powerful nozzle you’ll use. You’ll need to be very careful with this one. You can chip or etch your concrete driveway using the red nozzle.

Something like a metal shed requires a nozzle that is a little less powerful. A green tip (25 degrees) nozzle should suffice. If you want, try the yellow nozzle, but be careful. Give a small test patch a spray before proceeding with the entire cleaning.

Chemicals Needed

Depending on it you are just trying to remove rust or are trying to remove paint as well, will determine what types of chemicals to use. While technically not equipment, it is an aspect that needs to be taken into account. 

For rust removal, you may find you need of hydrochloric acid. This is the same type of acid that is used in your stomach, but a stronger version. Mixing with water can help to reduce the strength of hydrochloric acid. For paint removal, there are a variety of different paint strippers that can be used in conjunction with a pressure washer. 

Care must be used with these chemicals as they can cause significant burns, if not used carefully. Please keep the following precautions in mind. 

  • In case of getting hydrochloric acid on your skin, rinse well with water, remove any clothing that may have gotten hit as well. Serious burns should be seen by medical professionals. 
  • If you are concerned about the risk of hydrochloric acid getting onto your lawn or into the environment, you can use a mix of baking soda and water to neutralize it. Using a ratio of one part baking soda to ten parts water will help to render the acid harmless. 
  • After using hydrochloric acid, make sure to run a sprinkler on your lawn for a good hour or so, to ensure that the runoff does not damage the grass. 

Pressure Wash Rust Off

Pressure Wash Rust Off
  1. Connect the appropriate pressure washer nozzle.
  2. Select a small and inconspicuous area to conduct a test spray with the pressure washer. You want to make sure the force from the nozzle is not excessive where damage will be incurred.
  3. Work rusted areas with the pressure washer. The water pressure should be blasted away after several passes. Adjust your standing position or nozzle tip as needed for more or less water pressure.

Protect From Future Rust

Once the area has been allowed to dry completely, the following must be applied, allowing the area to dry completely between coats. 

  1. Apply primer
  2. Apply protective paint
  3. Apply top coat, if necessary. 

Preventing rust is not as hard as it may seem. From sealing concrete to properly treating areas that are prone to rust, preventing rust can actually be easier, and cheaper, than having to remove it periodically. Plus it has the added bonus of prolonging the longevity of anything that can and does rust. 

What is Rust?

What is Rust?

Rust is what happens when iron is in contact with water and air, also known as corrosion or  oxidation, or in more technical terms, iron oxide. The reddish powder that can coat improperly cared for cast iron pans is actually rust. 

Finding sources of rust

Rust can creep up on a number of surfaces and for a number of causes, though the number one cause is usually weather related. Wind and rain can cause damage to exterior surfaces and can cause the protective layer of paint or sealant to chip away. 

Places to check for rust:

  • Exterior walls, especially if they are made of or in contact with metal
  • Pipes both interior and exterior
  • Faucets and spigots
  • Check around your hot water heater as those can be rust prone due to constant contact with water.
  • Outside decorations that are metal such as metal yard decorations or metal bird baths.

Properly sealing to prevent rust

Once you have taken the step to remove any existing rust, the next step is to ensure that it will not return. Using a rust resistant paint or sealant can help to ensure that you do not have to worry about having to remove rust within the next year again. Prevention can actually save more time and money than most people realize. 

  • Proper painting can prevent rust from returning on small items such as lawn decorations. Use a good coat of primer and follow it up with a good coat of spray paint designed to prevent rust like some varieties of Rust-Oleum. 
  • If needed, also consider a clear top coat as well, just as extra protection from the elements. A top coat is not recommended for furniture as it can make the furniture slippery.
  • Some items that are constantly exposed to the element may require two coats of primer before you follow it up with rust resistant paint.
  • Large areas such as exterior walls would need a primer to prepare the area for painting after removing all of the previous paint and any rust. Make sure to remove all the rust you can cause trapped rust can cause the surface to rust under the paint. Using an airbrush sprayer can help to ensure that you have an even coat rather than thick areas and thin spots created by a brush. 
  • Large surfaces such as a concrete deck or concrete driveway will not be a cause of rust, but they are often the victims of it. Whether it is rust coming from a rusting source, such as run off from a metal gutter or is coming from your well water (if it has high iron content) sealing your driveway from additional rust after cleaning can prevent the reappearance of it. 

When is it a Good Time to Pressure Wash?

When is it a Good Time to Pressure Wash?

In some areas, the time of year is obvious, in others, maybe not so much. No matter where you live, it is something to consider. Both temperature and humidity need to be considered. 

Northern climates

If you live in an area that you get heavy amounts of snow (at least a foot through the winter), then running a pressure washer in the winter is not even much of an option. Late spring through early fall would be appropriate, depending on how far north you live. Although obviously climate change will factor into your local temperatures as well. 

Most of the time, the warmer the day, the quicker the project will dry. However, high humidity will negatively impact the drying times of paint and sealants.

Southern climates

The further south you go, the more the temperature may be an issue. While you may have daytime temperatures that reach the 60’s even in the middle of winter, the night temperatures may affect what you are trying to clean. 

If it drops cold enough to freeze overnight, then you may have issues with either your equipment or the surface you plan to clean as it may be easier to damage. 

On the opposite end of the seasonal scale, high temperatures along with the potentially high humidity can seriously affect drying time and may make working outside dangerous for those with certain health conditions. 

When Would a Professional Washer Be Better?

When Would a Professional Washer Be Better?

Some projects may be too big or too dangerous for the average consumer, which is why considering a professional is always an option. Even if you own your own pressure washer, certain projects can be dangerous for an inexperienced individual. 

So a few things to take into account would be:

  • The size of your project
  • Your budget
  • Your own experience with a pressure washer
  • The time you would have available to work on it
  • Safety precautions involved

What is the size of the project?

Determining the size of your project is important. No need to call a professional if it is just a few yard decorations that are large enough to pressure wash, but would take only a few minutes to clean. If you are planning to repaint the items anyways, then cleaning off the rust in the process just makes good sense. 

If it is a larger project, like a metal shed or even your driveway, it might be more advantageous to consider professional help with the project. Not only because of the time considerations, but also because of the experience level. Some surfaces can be damaged by the force of a pressure washer leading to damage, such as pitting or potential warping. 

What is your budget for this kind of project?

As in most things in life, money is always a consideration when taking on any project. If you are on a very tight budget, then hiring a professional may not even be an option for you. It wouldn’t hurt to get a free estimate on your project, even if you plan to do it yourself. A professional might have more insight into things to look for and extra steps your specific project would need. 

What is your experience level with a pressure washer?

Sometimes the issue is your own experience level. If you just bought your pressure washer last week, jumping into trying to remove paint and rust from a metal shed may be too difficult for you, at this stage. Taking time to properly learn and become familiar with your pressure washer could be a huge investment in your future. 

If you have owned your pressure washer, and have been using it pretty regularly, over the last few years, then you may be more aware of how high pressure will react to different surfaces. Having to replace a shed is almost always more expensive than hiring a professional to help. Sometimes just getting a consultation can help give you ideas on the best way to do it. 

Do you have the time available for this project?

Time is always something to consider when taking on a big project like this. If you can only work on it for a couple of hours in a month, then starting and stopping may end up causing more rust and eventually, more damage. 

If you are limited on time, then hiring a professional may make sense than trying to start and stop a project. In the long run, it could also save you money as well. 

How to Keep Safe While Pressure Washing

How to Keep Safe While Pressure Washing

Whether you are working on a small project or a larger one, whether you decide to do it yourself or hire a professional, there are always safety concerns that need to be taken into account.

Even if you hire a professional, having pets or young children outside while they work is never a good idea. It may sound like common sense, but a professional is trying to get the job done as quickly and safely as they can, and pets and kids can be a huge hindrance to that. So if you can keep pets indoors and children inside or out of the home while they work, this would be best. 

If you decide to do the project yourself, PPE (Personal Protection Equipment) should be worn at all times. From steel toe boots to safety glasses, you should always be sure you have the right safety equipment along with the equipment for the job. Safety should always be the first priority and the highest concern when working with high pressure and chemicals. 

Tips to Help You Pressure Wash Better

Tips to Help You Pressure Wash Better
  • Make sure to use PPE (Personal Protection Equipment) when working with a pressure washer, the entire time, every time. 
  • For spray painting any objects, large or small, please take care to use in a well ventilated area or use a breathing respirator to keep from inhaling the airborne toxins. Spray paint, and the chemicals involved can cause asphyxiation from lack of oxygen.  
  • Make sure to read any safety manuals and instruction manuals. This includes all safety precautions that are on any chemicals you plan to use as well. They could save life and limb. 
  • If you have well water, the rust could be from your water itself. Well water can have a lot of minerals in it, including iron. Not always a bad thing, but it can cause havoc on your property. Filters and softeners can help with this.
  • If you are having issues with a spigot causing the rust, it does not take much time or money to replace one. It can, however, save you a lot of time and money in the future. 
  • Be aware that if you are using a pressure washer to remove rust, any paint that is on the item will be removed as well, from the high pressure. So be prepared to repaint anything you are cleaning rust off of. 
  • Do not apply paint or sealant to a wet surface. The added moisture will prevent either one from adhering well.  It will need time to dry. A concrete driveway may need a full 24 hours to dry, while patio furniture can be completely dry in a matter of hours, depending on heat and humidity.