This is actually an improvement for my welding mask from earlier. It now fits onto a standard minifig helmet so the welder can flip it up. Imported the Football Face Gard by Leafprops in Blender for general form and to keep the "ear fittings".
I used a support structure to print it upright so the least important edge is facing down and cutting pliers to remove it (make sure to keep a bit of a knob on both sides for a good fit)
Used a policeman for the photos, would look better on a black helmet of course.
lego_welding_mask_v2.stl | 326.5KB |