Can Sandblasting remove rust?

 Yes, sandblasting can be used to remove rust; in fact, it is one of the best ways of clearing rust or corrosion from a metallic surface.

 

Sandblasting is a common technique used in many metalworks industries and workshops to clean hard surfaces, roughen a smooth surface, shape a surface or remove surface contaminants.

 

In this process, solid particles are forced across the hard surface at high speeds using compressed air.

 

It is an efficient method for removing rust. Sandblasting breaks down the rust on the surface and reveals the clean metal underneath.

Why is sandblasting better than other methods?

There are quite a few methods available out there for removing rust, electrolysis, manual wire brushing, or bristle blasting but the problem with all these methods is that they are extremely time-consuming and labour intensive.

 

These methods take tens of hours to remove rust and are only practical for smaller parts and in very limited quantities.

 

There are some chemical treatments also available on the market, but they contain harsh chemicals that could damage the metal. 

 

If you are looking to remove rust from large parts or do it on multiple parts regularly, then these methods are just not feasible for you.

 

That is where sandblasting comes into the picture.

 

If you operate a production shop, regularly perform rust removal on parts, or want a method to remove rust quickly and efficiently, then sandblasting is the way to go.

 

It can be of two types dry and wet, both of them are good options for removing rust, but wet abrasive blasting is the better option out of the two.

 

Dry sandblasting is a decent option and will get the job done much faster than all the methods mentioned above, but it has some limitations and drawbacks.

First, the abrasive particles could get stuck in the cracks on the surface, and second, the abrasive particles produce heat due to friction which could warp the metal, especially if it's thin.

Dust created in Dry Blasting 

 

These problems can be overcome using wet abrasive blasting along with a mild abrasive. This is the perfect way to quickly and efficiently remove rust from the metal surface without risking any surface damage. Another advantage of wet abrasive blasting is that it is dustless, and environmentally friendly as well as operator friendly. RapidBlast is the leading brand of wet abrasive blasting equipment and is known for its innovative technology and efficiency. 

 

Dust free Wet Abrasvie Blasting using the RapidBlast equipment

Best Abrasive Media for Removing Rust in Wet Blasting

Sandblasting gets its name from the fact that sand was used originally as an abrasive, but over the years, it has gotten replaced with other abrasives because it contains a high level of silica, which is detrimental to health, and it can be a little too harsh for some materials.

 

These days you will find materials like crushed glass, steel grit, nickel slag, walnut shells, and various types of plastics used as abrasive media. 

 

Before using sandblasting to remove rust, you should understand that rusting doesn't happen uniformly throughout the surface; instead, it follows a peak and valley pattern.

When you remove the rust from a surface, you might notice some small dents or dimples on the surface, this phenomenon is called pitting, and it is particularly found in ferrous metals.

 

If you are sandblasting a corroded aluminum surface, then crushed glass, walnut shells, and plastic media would be your best options. These materials have a lower Mohs hardness score and thus are a little more gentle on the surface and dont cause any damage to it.

 

For ferrous metals( iron or steel), you can consider using glass beads, aluminum oxide, or silicon carbide as they are harder materials and work better for these metals. Aluminum oxide and silicon carbide have pretty high Mohs hardness scores, so do keep that in mind when using them, as they can damage the metal surface if not used carefully.

 

If you are not sure if a particular surface can handle a more abrasive medium, it's best to start with a gentler sandblasting media and then decide if you want to move to a harsher material.

 

How To Remove Rust With Sand Blasting

Removing rust with sandblasting is a simple process involving a sandblaster and protective equipment. Here is the step-by-step process to remove rust by sandblasting:

 

Preparation Before Using Blaster

• Prepare the work area by securing it with a tarp to collect the used materials as they can be reused.
• Prepare the blaster by loading the abrasive media and closing all valves to prevent spilling.
• Protect yourself by covering your skin, eyes, and airways with safety gear. Use gloves, a respirator, a dust hood with protective lenses, and a blast helmet.

 

Using The Blaster

• Turn on the blaster and use it with short side-to-side movements and moving from top to bottom.
• Dispose of the material used to collect dust, and that tarp you laid down will have a lot of used material that can be used again for sandblasting.
• Protect the blasted surface as rust can return quickly if the blasted surface is not covered with some protective layer. You should clean the blasted surface of debris or dust and coat it with a protected finish.

 

Wet abrasive blasting can also cause flash rusting. To protect the surface from flash rust, you should add some rust inhibitor solutions such as RapidHold to the blast slurry and ensure that substrate is free from any contaminants. 

You should also consider applying a permanent protective coating to the surface after sandblasting to prevent rust from reappearing.

 

The Bottom Line:

Sandblasting is an excellent way of removing rust from metallic surfaces; it is a lot faster and more efficient than other methods like manual wire brushing. 

Sandblasting can be of two types dry and wet abrasive blasting. Both of them are good options for removing rust, but dry blasting has a few limitations which can be overcome using wet abrasive blasting; therefore, it is the better solution out of the two. It is the fastest and most efficient method for removing rust, but you should remember to use a rust inhibitor solution to prevent flash rusting.

And once the sandblasting is done, you should apply a protective coating to the surface to prevent the rust from coming back.