These wire rotary brushes are very cheap. I used them for cleaning rust and old paint off of some ironwork. Each brush would last less than 5 minutes. The steel bristles broke off way faster than they should have and they were not packed as thickly as reputable brands so there were fewer bristles to begin with. Maybe if i had been using them for softer materials they might have been more use. For my purposes this was basically money wasted.