The basic concept for this drilling frame came from Randy Knapp.   Although, this one is not a work of art like everything Randy makes.

The overhead drive powered drilling frame is made from 2-1/4"x.5" 6061 aluminum tube.  The tube inside diameter is bored a little to fit the outside diameter of the ball bearings.  The ER20 chuck has two drive pulley choices 2.5" and 1.24" diameter.   The drilling frame will fit in a Aloris type quick change tool post.   The ER20 chuck will accommodate from 3/32" to 1/2" diameter tools.   I really do like the even compression and self release feature of the ER spring collets.