Hideeho
Yes there is. If you push hard on the cutting wheel & it grabs it will hit the bearing. If you cut to deep you will cut into the bearing. Both of these are easy to avoid with light, firm preasure on the cutting head (allways the best advice when using a dremel, let the spped do the work, not the preasure), & paying close attention to what you are doing. A dremel is not going to kill or maim you like a chain saw or circular saw, but as long as you respect how quickly it will remove material & pay close attention to what you are doing, it is not a tool to be feared.