Bristle discs, or radial discs as they are often called are a great addition and oftentimes a decent substitute to sandpaper and polishing paper when finishing your jewelry.

The pros

• Quick to use: Easy to switch in and out of the flex shaft

• Flexible: They get in hard to sand spots that can be more time consuming to clean with sandpaper

• Clean: They are not very messy compared to the alternatives.

• Versatile: They range in grit from rough for sanding to very fine for a pretty good polish. 

The cons 

• Less control: Because of their flexibility, you can't control exactly where the bristles will go. This can be a problem if you are cleaning up near a stone. It also can create some waviness in your work if you aren't careful. 

• Shine:  You can't get the very highest shine possible. Although you can get quite close. 

Who they would be great for:

Anyone who wants to make a quick job of cleaning up a piece, get rid of scratches and put some shine, or even a matte finish on their jewelry, this is the perfect tool for. 

Who wouldn't benefit from them:

Someone with mirror finish aesthetic that includes crisp lines and angles. 

Using Bristle discs

When using your bristle discs, they work best when you have 3 or more on a mandrel. The direction they are placed on the mandrel is imperative. Put them on so that the ends are pointing toward the right. See picture below. The reason this needs to be done is because the flex shaft rotates counter clockwise. If you don't put the bristle discs in so that the ends face to the right, they will bend back agains your metal and break off very quickly, making them an expensive tool for you. But if you follow the correct direction for putting them on, you should enjoy using them for quite a while. 

Unscrew your mandril. They usually come with a washer in-between, I don't believe it makes any difference if you leave it in or not. 

Place 3 bristle discs pointing in the same direction on top of each other and make sure they are pointing in the same direction to the right.

Thread the mandril through and start polishing.