How to use a shot blasting machine?

Having a basic understanding of what shot blasting is and how it works will make it easier for you to achieve the profile that you’re looking for. The team at Surface Finishing Equipment Group can provide you with advice and guidance.

What is shot blasting?

Shot blasting is an easy method for cleaning, strengthening, polishing and preparing surfaces. It’s often adopted by many different industries, including aerospace, automotive, construction, shipbuilding and rail.

The blasting equipment supplied by SFEG, can be used to remove an existing coating of paint, rust or corrosion and has also been used for graffiti removal. It prepares the surface for a new coating of paint by etching the surface – allowing for effective, long-lasting adhesion.

If you’re lacking knowledge when it comes to using a shot blasting machine, SFEG can help you to understand the main concepts of shot blasting, including which shot to use and what speed to fling the shot at.

How does a shot blasting machine work?

A shot blasting machine is easy to use when you know how.

The machine is filled with abrasive media that will be propelled towards a surface.

The blast wheel rotates at speed and the abrasive media spins into the centre where it is accelerated and hurled in the direction of the surface that needs preparing.

Machines for shot blasting have a separation system that collects dust effectively – keeping the mess to a minimum. The dust collector removes contaminants and excess media and returns it to the storage hopper where it can be recycled and used in the future.

How to choose a ‘shot’?

The shot is fired from the blast wheel and there are three factors which can determine the best shot to create the desired profile, these are as follows;

• Size

The size of the shot has an effect on the profile/texture of the surface. Larger shots are ideal for heavy-duty applications.

• Speed

Another factor that impacts on the texture of the surface is the speed at which the shot is fired. Firing shots athigh speed ensures that the shot doesn’t hit the same spot repeatedly.

• Amount

The load is how much shot falls on the blade. Load size can be increased by opening the valve more – which will create more of a textured finish.

What are the different types of abrasives for shot blasting?

There are several different abrasives used for shot blasting and these are often dependent on the surface and chosen finish.

One of the most popular shot blasting abrasives is sand. As a coarse material, sand is ideal for hard surfaces that require deep cleaning or sanding –they aren’t suitable for soft surfaces.

Glass beads are also abrasives that are used for shot blasting. They are used as polishing agents which makes them perfect for delicate surfaces like plastic, metal, rubber and glass.

Small to medium-sized shots are ideal for removing glue as they prevent machines clogging up. If you’re looking to remove paint, a medium/large shot is the best option as it removes paint coatings quicker.

What are the safety precautions?

Shot blasting machines are carefully manufactured to make light work of preparing surfaces but they are surprisingly dangerous if not operated correctly.

When using a shot blasting machine, it’s recommended that you always wear PPE – including coveralls, a blast helmet and respiratory mask.

The blast room needs to be kept clean and well ventilated to eliminate hazards and make sure that work is carried out in a protective booth.

A shot blasting machine needs to be cleaned regularly to prevent it from functioning less efficient. The impeller also needs to be replaced to allow you to clean the machine.

If you need to know more about how to use a shot blasting machine, the team of experts at SFEG are always on hand to help, so be sure to contact them today.