by RetireeJay » 2015-Jan-Fri-11-Jan
Your buddy doesn't even understand the basics of 3D printer orientation. The only sane way to even attempt to print this would be with the large-diameter open circle in the X-Y plane, with the dome building up in the Z direction. Depending on the material you are using, the layer thickness, the trace width, and the use of fans, etc, the steepest "overhang" angle you can expect to do is between 45 and 60 degrees. Beyond that point, you're just dropping threads into the air. And printing this single-wall object with support (made of the same material on a single-printhead printer) is going to create a very messy object that will probably break before you can get it separated from the support.
I had a few minutes of spare time [Retired...] so I re-oriented your model in Netfabb and gave it a try. As I predicted, the overhang failed at about the 45 degree angle. I note that your model is only about 0.2mm thick. My nozzle (and therefore my minimum trace width) is 0.4mm, so the end product may have the right shape but there's no guarantee that it would fit on your doll-sized cup. In fact, achieving that precision is going to be difficult!
CoffeeCupLid-DiagonalView.jpg
CoffeeCupLid-TopView.jpg
CoffeeCupLid-SideView.jpg
You do not have the required permissions to view the files attached to this post.
Printrbot Plus operational January 2013
Brass threaded rods (5/16" X 18) & nuts for Z axis
GT2 belts & pulleys
Cable chain to reduce probability of fatigue failure in wires
E3D V5 Hot End, 0.4mm nozzle, also 0.8 and 0.25 in use occasionally
PB fan mount + 40mm fan -- using printed mount adapter, not the E3D supplied fan
Injection molded extruder gears
Optical Z "endstop" (custom designed and built)
Have used many pounds of T-Glase filament. Now also doing some work with Ninjaflex SemiFlex
Print on glass with Scotch Craft Stick or other glue stick
"My next printer is..." Prusa i3 MK3, upgraded to MK3S