Bead Blasting vs. Sandblasting: The Differences Between the Two Finishing Methods

Knowing the Difference between Bead Blasting and Sandblasting Matters

Sandblasting

The blasting process generally involves using equipment that can eject particles at high pressure to finish machined parts. However, this blasting process has different types, depending on the material contained in the high-pressure equipment. Knowing these different types is essential to know the best type to work with your machined parts. Good examples of blasting processes are bead blasting and sandblasting techniques.

While they both follow the same principles, these two processes differ in the blast media used and the type of finishes they give. In this article, we’ll explain both types of processes, the differences between bead blasting vs. sandblasting, and the safety considerations for both. If you want to know all about these two processes, this is the complete guide for you.

What is Bead Blasting?

Bead blasted parts

Bead blasting is a process that utilizes steel beads or glass beads to create a surface finish on a machined part. The process uses a blast gun that fires the blast media mentioned above at the part at high pressure.

The whole process occurs in a compartment known as a bead blasting cabinet. This cabinet helps to prevent the operator from being exposed to fragments of blast media flying off the machined part. Machinists commonly use this surface-finishing method for plastics, metals, glass, and rubber materials.

How does Bead Blasting Work?

As mentioned, the process involves shooting steel beads or a splintered glass against machined parts at high pressure. The blast media creates indentations on the parts, which go ahead to form the uniform finish.

The final result gives a satin or dull look, which could look either rough and consistent or smoother, depending on the coarseness of the blast media used. One good advantage of the bead blasting method is that it helps to hide any machine marks or imperfections on the part. This is because it would only give a color brighter than the original color of the part, hence, masking any disparities on its surface.

What is Sandblasting?

Sandblasting finishing parts

Sandblasting is another blasting process that uses sand as the blasting media. It also propels the blast media at high pressure and removes contaminants from the surface of the machined part. Sandblasting is the older method of both, as it was developed to upgrade hand sanding.

The process is also carried out in a sandblast cabinet, and the sand media used are sometimes reusable. The process is suitable for stripping older parts of their paint or rust, or it can also be used to prepare a part for a new finish. However, sandblasting services are becoming obsolete due to the health complications they can cause.

How does Sandblasting Work?

The sandblast finish also follows the same principle as bead blasting, using high pressure and a sandblast cabinet to prevent exposure. However, sandblasting is usually harsher on the metal surface and could affect the part’s dimensions.

Although it has advantages, its glaring downsides have made other blasting processes, like bead blasting, preferable recently.

Bead Blasting vs. Sandblasting: Which Should You Choose?

Glass blast vs Sandblast

If you’re torn between bead blasting or sandblasting as a surface finishing option, this section will explain a few factors to consider when choosing.

The Cycle Time for the Processes

Regarding the time needed for both processes, sandblasting is the better choice. It is faster, and sandblasting is the better choice if you need a process that can be completed quickly.

The Type of Material Used

Bead blasting uses steel beads or fine glass, while sandblasting utilizes sand. In this case, bead blasting is the better choice. This is because sand contains silica, which has harmful respiratory effects when exposed to humans. However, glass and beads don’t have harmful consequences; hence, they are safer for use.

The Abrasiveness of the Process

Sandblasting is the more abrasive process of the two, as it uses sand, an abrasive material. The abrasiveness of sand means it is harsher on the part’s surface and can cause changes in the part’s dimension. Hence, bead blasting is also the better choice here, considering abrasiveness, as it gives an optimum finish without damaging the part.

Differences in the Finishing Appearances

In terms of finishing appearances, bead blasting is also the better choice. This is because it gives an optimum and uniform finish without damaging the part. Due to the abrasiveness of the sandblasted metal finish, it is better suited to stripping parts of rust, old paint, or scales. Hence, using it as a final finishing procedure could produce poor part aesthetics.

Applications

As mentioned earlier, bead blasting can be used as a final surface finish for plastic, metal, rubber, or glass parts. On the other hand, sandblasting is more suited to removing impurities from the surface of parts.

Considering the factors highlighted, bead blasting is the better choice for both blasting processes. It gives a better finish and is gentler on the part’s surface.

Safety Considerations

When carrying out both processes, using a blasting cabinet and wearing protective gear such as gloves, overalls, and goggles is essential. However, due to the respiratory concerns that sandblasting has, it is usually avoided where possible. However, bead blasting is a much safer alternative; hence, manufacturers tend to go for it more.

Conclusion

Bead blasting and sandblasting are surface finishing options commonly used in machining. However, choosing between both could be a real task for many clients. If you’re having difficulty deciding the best choice for your machining project, please feel free to contact us with any questions.

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