My A1 keeps messing up prints. I’ve taken apart the hotend assembly, and put it back together. But, one of the screws will not tighten.
The one shown in the circle here. The screw itself is very short, I feel like it should be longer. Anyone know which size screw this should be?
That screw just screws into plastic & now that the hole has been rounded out I don’t think you will be able to get a screw to hold without some glue or thread locker.
Check to see if you put a screw in the wrong place:
Shave off a thin slice of filament, going along the length, not through the diameter. Long enough that when it bottoms out in the hole, a little still sticks out. Put it in the hole. That’ll give the screw something to bite and while it won’t resist over tightening, it should snug down and stay put. Drive the screw and see. 
