These are auger-style drywall anchors. They appear to me under my printing results to be sturdier than any other auger-style drywall anchor I've used. I will not certify a strength rating because your printing results and drywall conditions may vary, but the shape is quite robust. Significantly smaller commercial ones of similar shapes are rated for 75lbs on loads flush with the wall.
Instructions for use:
1) Make a little pilot hole. (You can drill, or just twist a screwdriver through drywall for this.) Make sure you're not in front of a stud, as anchors will not go into a stud.
2) Use the Phillips tip to screw the anchor directly into the drywall until it is flush with the surface.
3) Place what you are mounting and screw the metal screw into the hole centered in the Phillips tip of the anchor.
4) As the screw enters, the anchor will split open slightly on the inside part of the drywall, wedging it tightly in place.
I've often experienced the problem of some excess force removing an old anchor from a wall leaving a hole larger than the old anchors that were used. This requires either extensive effort to repair that part of the wall or if possible moving what was hung to a new spot. Or, you can simply print significantly larger anchors to fit in the new larger hole, which is what motivated this design. The included stl files are for anchors 20mm in diameter. Feel free to customize to your preferred sizing.
OpenSCAD Note: Download augeranchor.scad and v2 or higher of my threading library from http://www.thingiverse.com/thing:1686322 Rename the library download file to "threads.scad". In the future I am likely to only update the main threading library with updates to the threading routines, and I might not actively merge those changes with the customizer_version here.
Version 2 (2017-04-10) corresponds to the v2.1 auger thread bug fix of threads.scad. The resulting anchor should be effectively the same with both updated.
0.4mm x/y, 0.2mm z, 2.0mm perimeter, 1.0 top/bottom
Structural rigidity is essential, and solid infill should be used. The part is designed to crack open slightly at the pointy end, expanding inside the wall when the screw is inserted, and solid infill helps it keep its integrity during this process. Maintain adequately high printing temperatures so you do not experience delamination defects.