Are there Differences Between Shot Blasting Masks and Sandblasting Masks?

 
Even though they sound similar, there are enough differences between shot blasting and sandblasting that they require different names. It also makes sense therefore that the masks, also known as stencils, used for each type of abrasive work have some differences. Here, we’ll explore the differences between the two techniques, and then examine the different masks that each approach requires.

What is Sandblasting?

Despite the name, there is actually very little sand used in sandblasting. The name stems from the first uses of the technique for industrial engraving, when sand was the logical material for abrasive work. However, there have been many issues with using regular silica sand, from being affected by wind and humidity to the silica being a cancer risk when inhaled, that means that the “sand” used in sandblasting work is now a manufactured blend of minerals, metal, glass and even some natural materials like crushed walnut shells and corn cobs.

No matter what type of abrasive material is being used, sandblasting now refers to the technique of propelling the mixed media towards the desired surface with compressed air (hence the idea of “blasting”). The abrasive material comes out in a steady stream making it a great technique for engraving and stenciling, and the technology has come a long way so there’s no longer clouds of unhealthy dust to deal with in the process.

What is Shot Blasting?

The other main alternative to sandblasting for your industrial engraving projects is shot blasting. While the abrasive media remains roughly the same, the difference comes from the way that it’s applied to the surface. Shot blasting is a much more aggressive technique than sandblasting, as it uses devices like a spinning wheel that utilize centrifugal force to hurl the material at the desired surface (hence the idea of a “shot”). The mixed media comes out at a much higher force than with sandblasting, which makes shot blasting the technique of choice when you’ve got a very hard surface or a deeper level of engraving in your project. A shot blaster is also the tool of choice when it comes to larger projects.

How do Shot Blasting and Sandblasting Masks Differ?

Now that the differences between sandblasting and shot blasting have been explained, it’s clear that there have to be differences between the masks used for each type of work. A sandblasting or shot blasting mask refers to a stencil that you lay over the top of the material you’re working with that will protect it from the abrasive material. This means that you’re only cutting away at the desired indents of your pattern, leaving the rest of the surface clean and clear to make your design pop out. Here are some of the key differences between sandblasting and shot blasting masks:

• Flexibility – the first that you’d notice if you pick up a sandblasting stencil and a shot blasting stencil is the difference in flexibility. A shot blasting mask has to be more flexible to completely protect the components of the complex surfaces of your project against the high speed projectiles coming at it, while sandblasting can rely on a less-flexible stencil, as they only need to adhere to a flat surface to bring the intricate designs to life.
• Adhesive quality – another more subtle difference between sandblasting and shot blasting masks is their ability to stick to the target surface. Given the high impact of the abrasive material used in shot blasting, it’s no surprise that shot blasting stencils are designed to be highly adhesive so there’s no chance of them moving around during the project. While stencils are typically single-use, it’s crucial that they are easy to apply, maintaining the integrity of the design while remaining flexible enough to adapt to the surface without becoming overly rigid. In many cases with shot blasting, the surface is often coated with a protective layer which reacts with a lot of adhesives and so, it is very important to be selective with what is in the adhesive of shot blasting stencils.
• Durability – finally, shot blasting masks are designed to be considerably more durable than sandblasting masks. This gives you much better protection against the incoming abrasive media, but it can also drive up the price of the stencil. You’ll also find that shot blasting stencils will withstand the heavy beating of a single large scale project, while keeping your design clean and precise. Sandblasting stencils are less durable, as they don’t need to withstand such high velocities, but it’s still important for them to be hard wearing to fully protect the material underneath the stencil.