How often should I replace my steel brush?
Dremel steel brushes are designed to last 50-100 hours. For those who aggressively use their steel brush, you may need more frequent replacement. Dremel advises that users check their steel brushes after every 30 hours of use. Replace your steel brush when the carbon steel piece is shorter than 1/8 of an inch. After replacement, please turn on the tool for 5-10 minutes to make sure the steel brush is properly seated.;