Had my first crash last night and now I'm getting some noise from the spindle (bearing I suspect) I was doing a simple drilling op in 1/16 aluminum sheet and forgot to set Z on the tool. First holes were drilled in air to the right of the vice and clearly I spaced and did not realized the tool holder was below the material. Feed was at 40-50%, tool was a drill chuck with a fairly long stick out (4.5 inches) and as it moved to the next hole, about two inches away, the chuck jaws began to chew into the aluminum and the perimeter of the chuck got into the hard step. X axis errored out for load and everything shut down before I could hit the estop.

All the axis seem fine and they didn't make any noise or act funny. Checked the spindle bore for runout and it was unchanged from previous readings (virtually zero on a .0005 indicator) Also tried it on a tool shank and it was much the same as what it has been previously. If the spindle is ran blow 50 or so rpm it sounds as it always has but as you speed up there is a very clear rattling noise.

Is there a chance the bearings could be damaged without effecting runout? Could that noise be caused by something other than the bearings? I didn't try running it after as it was late and I was pretty bummed about the whole thing.

Video here of me spinning it by hand, can hear the rattling at the end of the video.

https://youtu.be/UMygRYywS1o