While "Hoggin'" out some aluminum material the chuck assembly just popped out! I thought the bolt sheared off or something but upon closer inspection I noticed that the chuck was just fitted onto a tapered shaft, so I retracted the jaws back to expose a flat surface and the took a dead blow mallet to it for 2 strokes and it has stayed ever since but of course I was using a 1/4" deburr bit and I haven't tried it again. So be aware of that. Other than that, it is a great tool at a great price!