Hello, I have made these goggles and I want to make a boss extrude from a multiple face double curved surface. The only way I know how to do this is by curving a sketch on a surface and making this in a 3d sketch. This is because I can't select multiple faces when selecting 'up to surface' with a normal boss extrude from a plane.

For some weird reason the boss extrude gets a weird shape, and I do not know how to avoid this.

Also I am in a bit of a hurry, because I want to start 3d printing this goggles today.

I have added the file aswel, please forgive all the errors, once everything is in place I will backtrack and fix them.