Bead blasting is a surface finishing process that utilizes small spherical media (normally glass beads) to clean and finish a workpiece. It is different from The other more aggressive technique like sandblasting. What is the difference? We will explore this in more detail. Let us dive in.
What is Bead Blasting?
In the bead balsting process, the bead-shaped media is propelled at high velocity by a high-pressure tool, and then it shoots toward the surface of
the material, cleaning the dirt, smoothing sharp edges, and creating a
uniform matte finish.
The typically used abrasive media is small glass or ceramic or plastic beads.
How Does the Bead Blasting Work?
The bead blasting process is similar to that of the other abrasive blasting methods.
Generally, it involves propelling spherical or bead-shaped media at high
velocity against the surface of a workpiece.
The dimpling impact of the bead blasting media creates the desired finish
or texture on the material’s surface.
Here are some key steps for the bead blasting process:
Preparation
Clean the workpiece to remove any grease, oil, or other contaminants that could impact the blasting process.
Abrasive Beads Selection
The choice of bead blasting media depends on the material being blasted
and the desired finish.
For example, glass bead blasting can produce a smooth and satin-like
finish, while ceramic bead blasting is suitable for applications requiring
a more aggressive surface finish.
Blasting
The bead blasting media is propelled to high velocity by a blasting gun
using compressed air, it shoots towards the material’s surface, removing contaminants, cleaning surfaces from dirt, and creating a smooth and
clean surface.
Post-blasting
When the bead blasting process is completed, typically, the surface will be cleaned to remove the remaining abrasive particles.
Coatings or other finishes may be applied to the workpiece to protect the bead-blasted surface further.
What is Sandblasting?
Sandblasting is another surface finish technique that uses a very high-pressure tool to propel the granular media at high speed to hit the surface being treated.
Traditionally, sand was the media of choice, but various other granular media are used now, depending on the application and desired surface finish.
Sandblasting is a versatile surface finishing process in various industries, it
is used for removing rust and corrosion in shipbuilding, removing concrete soiling and preparing metal structures for protective coating in construction, and etching designs onto glass in artistic sculpting.
In comparison to the bead blasting process, sandblasting is more faster and powerful in handling tough materials and rugged surfaces.
Bead Blasting vs Sandblasting: What Is the Difference?
Both sandblasting and bead blasting are efficient surface finishing techniques, the main difference between these two processes is that sandblasting uses abrasive material like sand, whereas bead blasting uses fine small media like glass beads.
When deciding which surface finishing process is better for your project, it is important to know the key differences between the sandblasting and bead blasting processes.
Let us look at the below table.
Criteria | Sandblasting | Bead blasting |
Abrasive Media | Sand grains, Silicon Carbide, Aluminum Oxide | Glass beads, Ceramic beads, Plastic beads. |
Abrasive Size | Larger | Smaller |
Material Removal | More | Less |
Surface Finishing | Harsher, Rougher | Gentler, Smoother |
Potential Surface Damage | More | Less |
Dust Production | More and require powerful dust collection systems. | Less and easy for dust collection. |
Risk of Contamination | Higher risk of contaminating with abrasive particles. | Lower risk of contamination due to the softer media and gentler process. |
Application | Heavy-duty applications,such as industrial cleaning and rust removal. | Lighter applications, like smooth surface preparation, delicate materials. |
Benefits of Bead Blasting.
Bead blasting offers a range of benefits, making it a preferred choice for specific applications. Some of the key benefits include:
Dimensional stability.
Bead blasting is recognized as a gentle finishing process, this process
is not as aggressive as the other abrasive blasting methods. It helps to
achieve a uniform surface finish without impacting the dimensions of
the parts.
Due to the gentle nature of bead blasting, it is widely used in dealing
with delicate materials like aluminum and plastic, It is also suitable for applications requiring fine polishing without deep abrasion.
Environmentally friendly.
The abrasive materials used for the bead blasting process are Eco-friendly, such as lead-free glass beads. It is recyclable and complies with environmental regulations.
Versatile finishing options.
The bead blasting process achieves a finish that can be considered rough
but consistent, it depends on the size of abrasive media used.
Firstly, Bead blasting, using a smaller media, gives the material surface a smooth and satin-like finish without damaging the workpiece.
On the other hand, medium-size beads are suitable to deal with metal materials such as stainless steel and aluminum, they create a matte finish which helps to hide any form of imperfections on the component surfaces.
Lastly, Larger beads are the best choice for eliminating burrs and cleaning rough surfaces on metal castings. It produces a textured surface finish.
Advantages of Sandblasting.
Sandblasting is one of the most common surface finishing techniques.
Due to its aggressive nature and a wide range of abrasive media options,
the sandblasting process offers a range of advantages:
High Efficient.
Sandblasting can quickly remove rust and old paint, clean large surface
areas, and require less manual labor, making it an efficient solution for
surface preparation in various industrial applications.
Various Surface Finishes Options.
By using different kinds of abrasive media, sandblasting offers a range of surface finishing options. When dealing with heavy rust removal and other rough finishes, steel grit is the choice, however, if you need to etch designs
on glass and stone surfaces for the purposes of decoration, aluminum oxide media is preferred.
Versatility in Applications.
Sandblasting is a versatile process that is suitable for many applications in various industries. It is commonly used for removing old paint and cleaning hulls in the shipbuilding industry, for surface preparation in the automotive industry, and for removing concrete soiling in the construction industry.
Tips to Get Quality Bead Blast Finishes.
Specify the Abrasive Media Types and Size.
When determining which abrasive media type and size are better for your project, the answer should be what the desired finish is and the material
being blasted.
Suppose you are looking for a smooth, satin-like finish without damaging
the underlying surface, fine glass beads will be the choice.
On the other hand, if you need a rougher finish to mask the imperfections
on the workpiece surface, it is better to select coarse ceramic beads.
Generally, the abrasive media sizes can be classified as very fine, fine,
medium, or coarse. The selection depends on the surface requirement.
Cover the Key Features.
Some features of the workpiece may require highly accurate dimensions
and surface finish, such as threaded holes, o-ring grooves, and surfaces
that require sealing. When doing the bead blasting process, you should
mask those features to avoid affecting them. It is better to note the
masking requirements on the drawings.
Use Low Pressure for Glass Bead Blasting
The working pressure range for glass bead blasting is 40-80 PSI normally,
it would suggest setting the pressure at 50 PSI which will help to increase
the lifespan of beads and get an optimum surface finish.
The beads will be smashed when impacting the workpiece at high working pressure, resulting in higher processing costs. Furthermore, it will produce excess debris and sharp particles, leading to degraded finishes due to some crushed particles embedded on the workpiece’s surface.
Remove Oxides or Rusts Before the Bead Blasting process
The glass beads are not designed for cutting, instead, they are made to polish a part. The glass bead blasting process can’t remove or strip off the oxide layer on the surface of the aluminum component, because the oxide layer is too difficult to be burnished by the glass beads.
Therefore, you need to use a sharp cutting abrasive like crushed glass, silicon carbide, or aluminum oxide to get rid of the hard oxide layer before proceeding with bead blasting on aluminum parts.
Conclusion:
Both the bead blasting and sandblasting processes can be utilized to
clean and finish the workpieces in a wide range of industries, however,
each surface finishing technique offers its unique advantages and creates different surface finish.
Understanding the differences between bead blasting and sandblasting processes will help to choose the suitable process for your project to
achieve the desired surface finish at a lower cost.
This article also includes the tips to get quality glass bead blasting finishes,
it is worth considering those tips if you are looking for the best bead blasting finish on your parts.
Reach out to us if you have any cnc machined parts that required bead
blasting or sandblasting finishes.
Bead Blast Finish FAQs.
What are the main differences between bead blasting and sandblasting?
Bead blasting uses smaller abrasive materials like glass beads, whereas sandblasting utilizes larger size media like sand.
Also, bead blasting is a gentler process which fit for lighter applications,
but sandblasting is more aggressive which suits applications that require
more material removal.
What is commonly used abrasive media for bead blasting?
The first one is lead-free glass beads that are used to produce a smooth
and satin-like finish.
The second one is ceramic beads which are suited for creating a rougher finish.
The third one is plastic beads, this media is ideal for delicate or sensitive surfaces.
What factors to consider when choosing between sandblasting and bead blasting?
The right surface finishing technique will help to get the expected finish
quickly and cost-effectively, how to select?
Some factors are listed as follows:
1) . Desired surface finish
2) . Material sensitively
3) . How much material is to be removed by the process
4) . Environmental impact
5) . Health and safety concerns
Reference:
Wikipedia.