[drew1]

A Rigid Pipe Threading Machine with a 1/4 Bolt Die would work. Comercial Electrical Shops & Plumping Shops probaly have the machine & may have the die for threading hangers.

Another way if the fab shop you're working in has a lathe with a reversing switch, is to make a die holder for a 1/4 round adjustable die. Hex dies are mainly for chasing damaged threads & are hard to get good threads with.

To make the die holder, buy a die at a machine tool store & make the holder to fit the OD of the die. The holder should 1/2" bigger than the OD of the die for set screws to secure the die. Drill a good sized hole into the end of the stock you are making holder for, deep enough to take care of thread length. You want room for chips. Bore a hole a few thousandths bigger than the OD of die, back to a shoulder to a depth of the thickness of the die. On the other end turn back an 1 1/4 to 1 1/2" a diameter you can mount the holder in a drill chuck on the lathe. Drill & tap set screw holes to match the dimples in the die to secure it in the holder. Drill a good sized hole to get chips out of the holder.

To use, mount the holder & die in chuck in the tail stock spindle. Loosen up tail stock so it slides freely. Put the rod in the lathe chuck & run at slow speed. Push the tailstock until the die engages the threads. The die threading on the rod will pull the tailstock. Stop when you have threadlength wanted. Then reserse the direction of spindle rotation to back the tailstock & die off.