Fenwick stopped selling blanks back in the real early 90's if I remember right. The HMG fly rods were some of the very first graphite rods made. I'd make my ferrule wrap at least 2 times the OD of the ferrule's end and place it as close to the edge as you think you can get it.I can get mine pretty close to a mm from the edge by packing the thread with my right thumb as I keep the thread from going over the edge with my left thumb and thumbnail plugging the ferrule's hole.