19mm spool holder flashforge creator pro

I received some Nylon filament with a spool with a 19mm center hole. Not having any spool holders that small, I drew this up to mount the spool on the back of my flashforge creator pro. It mounts through the hole on the back and the original m30 nut holds it in place. I don't need anything holding the spool on the holder since my printer backs up against a wall, and the spool has nowhere to go.j
I use this for Taulman 618 nylon