Quite some time ago, we posted a blog about Anchor Profile. This post explained what that is and why it is important.
The picture above clearly demonstrates the differences in anchor or etch profile using different mesh sizes of Aluminum Oxide Grit. All of these coupons are aluminum metal.
The top left was blasted with a 36 Mesh grade. This produces a rough looking and rough feeling surface finish. While all these blasted parts will look like sharp peaks and low valleys on the micro scale, on this coupon you can see that with just a simple 10x jewelry lens.
The upper right was etched with 120 Mesh. While you can still see some etching on this example, the surface feels much smoother and more uniform.
While still etched, the bottom example which was blasted with 220 Mesh has a very uniform, frosted finish. This is a finish often seen on frosted glasses, signs, and windows.
Selecting the proper grade of abrasive media is important to ensure you get the proper surface profile based on either next steps, such as a coating, or simply just an aesthetic finish.