Glass Media Differences

Probably the most important aspect of any finishing project is deciding on the proper blasting media to use. Anything too rough could harm your surface, but media that is too soft may not perform as needed. From organic grit to material abrasive – Kramer Industries has a broad range of media to choose from. In this post, we’ll break down the difference between two popular types of glass: glass beads and crushed glass grit.

When to Use Glass Beads for Finishing

Glass beads are ideal for completing metal surfaces and are versatile for tasks like glass cleaning, frosting, and etching. These are the main purposes:

Cleaning: Cleaning is perfect for preparing surfaces without changing the size of the workpiece or introducing iron contaminants. Glass beads are ideal for keeping close tolerances because they are gentle and non-abrasive.

Finishing: Various sizes of glass beads enable a diverse selection of surface textures. They are able to eliminate machining marks and create a uniform, satin-like finish, which makes them ideal for aesthetic purposes.

Peening: Glass beads are commonly applied to lessen tension in metal parts, boosting their ability to withstand fatigue. This procedure enhances the material by creating compressive stress.

Deburring: Glass beads are able to eliminate burrs from components while maintaining a smooth, polished surface. This is advantageous for accurate parts where surface quality is crucial.

Environmental Benefits

Glass beads do not contain free silica, a common worry in traditional sandblasting media, making them eco-friendly. This makes them a safer choice for workers, as free silica can emit harmful chemicals that lead to respiratory problems.

Factors to Consider

Bead size
Shape of the workpiece
Blast nozzle distance
Air pressure
Type of blasting system

If glass beads are handled correctly, they can be reused numerous times, minimizing waste and lowering expenses. Utilizing glass beads results in a shiny, sleek, satin finish and also helps in cutting down on cycles, thus saving both time and money. Experienced suppliers can assist in deciding between coarser or finer beads based on the desired finish for high-volume blasting operations.

In general, glass beads are a great option for obtaining a smoothed surface, which makes them flexible and budget-friendly for different industrial uses.

When to Use Crushed Glass for Finishing

Crushed glass is a highly effective abrasive for surface preparation, particularly when you plan to apply coatings afterward. Its irregular, angular shape provides a more aggressive etch, making it ideal for roughening surfaces and ensuring coatings like paint or sealants adhere well.

Here are key uses:

Surface Preparation: Prepping the surface with crushed glass can produce a roughened surface that improves adhesion for future coatings. It is especially successful in eliminating rust, old paint, and additional surface impurities, making it appropriate for industrial or structural uses.

Environmentally Friendly: Manufactured from 100% recycled glass, crushed glass can be used again and again and disposed of in the environment after use in an eco-friendly fashion. It is non-toxic and helps minimize pollution, making it a good option for blasting.

Health Benefits: Crushed glass has less than 1% free silica compared to silica sand, which can contain up to 99% free silica, thus decreasing the chance of respiratory diseases significantly. It does not have any harmful metals such as beryllium, which is often present in other abrasives like slag.

Non-Reactive Properties: Crushed glass is chemically inert, meaning it won’t cause chemical reactions like rust back on metal surfaces. It’s safe to use around water and other sensitive environments, further enhancing its versatility.

Post-Blast Finish: The natural, white post-blast finish left by the crushed glass can serve as a final attractive step in finishing. It creates a clean, textured surface with minimal embedment, meaning fewer particles get lodged into the workpiece compared to slag.

Cost Efficiency: Since crushed glass is less dense than other abrasives, you’ll use less material during blasting, reducing media costs. Its translucence also improves visibility during blasting, increasing productivity.

Safety and Approvals

Crushed glass is SSPC AB-1 Class A and MIL-A-22262B(SH) approved for toxicological safety, ensuring it’s a safe option for many industries. It is often chosen for industrial finishing projects, including marine, automotive, and architectural applications where both safety and environmental impact are critical concerns.

In summary, use crushed glass when you need an aggressive surface preparation for coatings, especially when environmental safety, health considerations, and cost efficiency are priorities.

Size	Mil Finish Range	Typical Mil Finish	SSPC-AB1 Grade	Applications
Medium	1.0 – 2.5 MILS	2.3 MIL	Grade 2	Automotive, dustless blasting, soda blast alternative. Smooth, white finish.
Medium – Coarse	2.5 – 3.5 MILS	3.1 MIL	Grade 3	Bridges, tanks, steel construction, precast concrete.
Coarse	3.5 – 4.5 MILS	3.8 MIL	Grade 4	Deeper profile for bridges, tanks, steel construction, and precast concrete.

This guide shows how different sizes of crushed glass create varying surface profiles, tailored to specific industries and applications.

FAQs

Are glass beads safe for sandblasting?

Glass Beads are generally considered safe for sandblasting. They are a popular choice for surface cleaning and preparation because they are environmentally friendly, non-toxic, and inert. Glass Beads are also reusable and can be recycled multiple times. This makes Glass Beads a cost-effective option.

Additionally, Glass Beads are a softer abrasive blasting media than some other options, such as Aluminum Oxide Grit or Steel Shot. This means Glass Beads are less likely to damage or distort the surface being treated. As with any abrasive blasting media, it is important to follow proper safety precautions, including wearing appropriate personal protective equipment, working in a well-ventilated area, and following the manufacturer’s instructions for use.

Will glass beads remove rust?

Glass Beads can be effective at removing light rust or rust stains from a surface. For heavier rust or corrosion, a more aggressive abrasive media such as Aluminum Oxide Grit or Steel Shot may be necessary. The effectiveness of Glass Beads in removing rust can also depend on factors such as how heavy the rust is and the required final surface profile needed.

Is bead blasting better than sandblasting?

Whether Glass Bead blasting or sandblasting (abrasive blasting) is better depends on the specific application and the surface being treated. Both Glass Bead blasting and sandblasting are blasting techniques that use different media to clean, polish, or prepare a surface for further treatment.

Glass Bead blasting uses spherical beads that are propelled at high speed to remove surface contaminants or improve surface texture (i.e., peening). Bead blasting is often used to remove paint, corrosion, or scale from metal surfaces, to clean and polish delicate surfaces such as aluminum or titanium, or to create a matte or satin finish on a surface.

Sandblasting uses hard, angular particles or other hard, sharp-edged particles, such as Copper Slag, Garnet Grit, Aluminum Oxide Grit, or Silicon Carbide Grit to clean and prepare surfaces. Sandblasting is often used for heavy-duty applications such as removing heavy rust, scale or corrosion from metal surfaces, or preparing surfaces for coatings or paint.

In general, Glass Bead blasting is a more delicate process that is ideal for softer surfaces or surfaces that require a lighter touch, while sandblasting is more aggressive and better suited for heavy-duty applications. The choice of abrasive blasting technique depends on the specific surface being treated, the desired end result, and the type of equipment and media available.

Choose Glass Abrasives from Kramer Industries

Select glass abrasives provided by Kramer Industries for top-notch, environmentally friendly blasting solutions designed to meet different surface preparation requirements. Their glass abrasives are perfect for achieving a polished surface, offering various levels of abrasiveness and the ability to be reused, resulting in lower expenses and waste. Kramer Industries provides professional advice to assist you in choosing the ideal abrasive for your particular needs.