I needed a small chuck to use with really small drills. All the nicely made 3 jaws I had would not close up on small drills. I took the chuck out of an old Makita and turned the shaft to 3/8". I have not even tried to measure run out as it works awesome in the smallest work. I regularly use #50-60 drill bits and sometimes even smaller.
I use it with a collet in the mini mill but I have also mounted in a drill press, works great.
I use it with a collet in the mini mill but I have also mounted in a drill press, works great.
) I have mounted chucks similar to what you have done but I added a Tru Adjust feature to the mount which allows me to zero out any runout. I have one mounted on a MT1 shank for my Atlas Craftsman 6 x 18 lathe and another on a 3/8" straight shank for the mill.
