I know, maybe it’s boring but i print my first case for an Raspberry Zero. So cute, here some pics … but i had a Problem, the center sides of the lid’s under the hinges are glue together. I fixed this with a sharp blade and a hammer 
How can i fix this, may i have to calibrate my printer?
That’s beautiful. I was wondering when originally looking at the Raspberry if there would be a case available. Great job!
Maybe need to tune the extrusion rate esp if the parts are drawn close together. Or just draw it with more space between the parts.
Calibrate you extruder. Here’s a simple guide: