a set of the over-ear-holder-pieces for my particular set of glasses… make and model no longer intelligable. 

can be printed without supports and with a standard 0.4mm nozzle at 0.2mm layer height. with a cool plate you do not even need a brim.

in my case the side with the drill hole for the mounting screw is the inside and i decided to print with that side down. 

i printed them in PETG in a matte old gold metallic color as that is the darkest tone of PETG i have around and since in PETG hot summer days should not cause it to deform. 

the piece is designed flat but will most definitely need adjusting this is done by heating up the pieces at about center of the long side with a hotair gun (from a soldering station) set to max airflow at 110degC at close proximity and over 10-20mm of length (min). monitor the material carefully once the weight of the rear causes the material to deform remove the heat and bend into shape by hand – go slow and do not overdo it it takes only small adjustments and the process can easily be repeated several times without causing too much of an issue. Likewise proceed with by bending the short side into shape after heating right at the bend (this is by the way not much different in principle to how professional opticians would do it from what i've seen like 20years ago…)

i decided to print with cocentric top and bottom pattern and it feels like the finish is slightly better than with the default “monotonic” setting but eitherway you WILL want to spend some quality time with the part and the finest grit sandpaper you have (just going over it with a razorblade might also make it bearable – the smallest kink or surface imperfection will cause an irritating feel. you might even want to print on PET sticky tape for a super glossy (and thus smooth) finish to reduce the need for post processing but i did not try.

infill pattern and density are not critically important 15% w/ adaptive cubic works well for me. 

The entire print is ~5mins (!)

since the make and model of my glasses is no longer identifiable this is more of a showcase what is possible and how then any thing else