E3D V6 collar mount wasn't fitting even after messing with flow on cura. Made the hole bigger 0.15mm bigger, so it fits snugly on my E3D. Included .f3d file so you can adjust it yourself. I suggest to print the original, and then adjust the hole in 0.05mm increments. You can also use a digital caliper and adjust the offset based on that. I have 0.40mm offset and it fits snugly (Mount 16,30mm and hotend 15,90mm).
The author remixed this model.