Wet blasting the right way: Master sandblasting with a pressure washer
Wet blasting removes dirt from durable surfaces. We show you how to achieve optimum results.
01.10.2024
Special blasting granulate is used for wet blasting. The mixture should be adapted for effective sandblasting with a high-pressure cleaner and should be of the correct grain size. Ready-to-use granulate mixtures are available ready for immediate use.
A grain size of 0.2 to 1.0 millimetres is suitable for wet blasting if you use the STIHL wet sandblasting set.
The pressure used during wet blasting varies. Depending on the type and properties of the material to be cleaned and the degree of soiling, low pressure may be sufficient to achieve good results. If needed, increase the pressure for enhanced cleaning performance. But be aware that excessive pressure can damage the surface being cleaned, so you should take a cautious approach.
What is wet blasting?
Wet blasting refers to sandblasting with a pressure washer. Sand granulate is used to clean durable surfaces such as metal, stone and concrete. In contrast to sandblasting with compressed air, this cleaning technology uses a mixture of water and blasting granulate.
Areas of use: When is it worth sandblasting with a pressure Washer?
Wet blasting essentially works a little like sandpaper. High-pressure sandblasting removes rust and dirt from durable surfaces such as metal, stone and concrete. While grinding machines are great for cleaning flat surfaces, wet blasting with a high-pressure washer is best for uneven surfaces.
So ideal areas of application for wet sandblasting include:
Corrugated metal fences
Dirty masonry
Small, durable metal parts
What you need for wet blasting
There are three essential components for wet sandblasting: a high-pressure cleaner, a wet sandblasting attachment, and appropriate sand granulate such as STIHL SB 90 blasting granulate. With these tools you’ll be well equipped to remove even stubborn dirt without leaving any residue.
Instructions: How sandblasting with pressure washers works
Before you start the actual wet sandblasting, you should prepare the surface for cleaning.
For example, if you want to remove rust from a metal fence, first disassemble it into its individual elements. Spread out a tarpaulin to collect the removed rust and blasting granulate, and dispose of them properly after the work has been completed. This preparation also ensures that you can maintain an optimum distance at all times and that the blasting granulate only hits the surface to be cleaned; delicate plants in the flowerbed behind the fence remain protected.
Working with high-performance power tools is fun and allows you to broaden your skills, which is great if you can rely on effective and safe protective clothing. Always wear your personal protective equipment when working with high-pressure cleaners. This includes safety glasses, non-slip footwear, gloves and more. Find out more information in the operating instructions for your product. Before using your power tool for the first time, fully familiarise yourself with it and ensure that it is in flawless condition before each use. On request, your STIHL dealer will be happy to prepare your power tool for its first job, and will also advise you on models and sizes of protective clothing that you can try on at your leisure. Please remember that personal protective equipment is no substitute for working safely.
Preparing the high-pressure cleaner
Before starting up your high-pressure washer, make it ready for use as usual. Then fit the wet sandblasting attachment to it; attach it directly to the spray lance of your high-pressure cleaner, in place of the nozzle. Insert the other end of the wet sand-blasting attachment into a bucket containing the appropriate blasting granulate. The optimum quantity of granulate is automatically conveyed via the hose.
Only use suitable and non-hazardous sand granules for wet blasting. Avoid sandblasting with quartz sand in particular.
When sandblasting with a high-pressure cleaner the effective area is a circle of about three centimetres in diameter. With this in mind, move the jet slowly over the surface to be cleaned, as if in slow motion, so that the mixture of water and blasting granulate can effectively remove the dirt. For stubborn dirt, carefully increase the pressure or repeat the process.
After use, empty the granulate hose.
Do not switch off your high-pressure cleaner immediately after work has been completed. First remove the end of the hose from the granulate bucket and then press and hold the spray gun until the granulate has completely drained out of the hose. The wet sandblasting set has now been emptied and is ready for storage, and then the next use for wet sandblasting with a high-pressure cleaner.
Finally, dispose of the collected dirt and the blasting granulate properly.
