I'm planning on doing Kumagawa too, and I decided to go with using Great Stuff expanding foam (which you can get for about 5 bucks a can at any home improvement store) around a piece of pvc pipe. I plan on making a ring out of posterboard that will be the width of the screw shaft to use as a reference, then covering the majority of the pvc pipe with enough foam to make it a little thicker than the size I want so then I can carve off the excess and make it round. I'll do something similar for the head of the screw, making a ring and using that as a guide before covering the small amount of pvc still uncovered with more foam, then carving out the shape I want. Once I finish carving, I can fill in any big gaps with more foam, then cover it with papier mache. I am still working out how to make the threads, but I will be sure to let you know what I come up with and how well this method ends up working for me! Hope all that made sense!
Klaus Von Reinherz - BloodBlockade Battlefront
Kirito - Sword Art Online II
Asahi Kuromine - Actually, I Am...
Triceracop - Kung Fury
Anime Weekend Atlanta
Klaus Von Reinherz - Blood Blockade Battlefront
Ginoza Nobuchika - Psycho-Pass
Sting Eucliffe - Fairy Tail
Jaune Arc - RWBY