Something needs to lock the pipe collar to the drill heel and give leverage to rotate the drill press when cutting the wire. I chose something very simple.
The holes in the chuck for the chuck key are 5/16 inches in diameter. I used the end of a drill to determine the size. See first photo .
I used a digital caliper to determine the distance between the bottom of the part of the chuck turned with the chuck key and the center of the hole for the chuck key. second photo shows a weak line scratched in the outer surface of the black tube collar. I used a spring loaded center ball to drill exactly on that line.
I started with a very small drill and worked up to larger pieces until I drilled a hole about right to lose to make wires for a 5/1
Test the fit with a 5/16 inch bolt. See fourth photo . The end of the bolt is screwed into the hole for the chuck key.