An elegant Christmas ornament with complex patterns and many details.

Here's a design I created a while ago, but never shared online. I found it while decorating my tree this year. I decided it was too good to keep to myself. I've provided updated PrusaSlicer 3MF and Prusa MK3S+ GCODE files. I tested the new settings by printing just the top of the ornament and they solved the problems with gaps. I'm now printing the whole ornament. I reduced the printing speed, increased the hot end temperature, increased the extrusion multiplier (flow), and added extra top layers in a small area. You may need to adjust these for your printer and filament. The version of the ornament shown in the photo was printed with older settings that was lighter but may be prone to break after printing.

If you open my 3MF file in any slicer other than PrusaSlicer, you'll need to carefully inspect the sliced model for things that could fail – like missing supports or parts of layers that need infill. I'm reasonably certain that Bambu Studio can open my 3MF file, but will not honor all the settings in it. There may be other slicers that behave similarly.

Print Settings

My default settings are:

• Top and Bottom Solid Layers: 2
• Perimeters:1
• Infill: 0%
• Support Overhang Threshold: 32 degrees

I used shape and height range modifiers to change these settings just where it was needed. For details, keep reading.

For comparison, using 2 perimeters everywhere, adding 30% infill everywhere and setting top and bottom to 5 everywhere more than doubles the print time and triples the weight.

Supports – You must print this with supports. Without them, it will fail. Even of your printer can handle extreme overhangs, the print will be ripped from the build plate before it is halfway done without supports to hold it in place. I also reduced the gap between the supports and the model from the default 0.2mm to 0.1mm.

Infill – There are a few areas in this model that need infill, but they're just a small part of the whole model. I used an STL file and height range modifiers to add 30% rectilinear infill in just the areas that need it – scaling it up and down as needed. I've included my infill STL (infill_docunt.stl) in case you use a slicer that supports STLs as shape modifiers.

Bottom of the Ornament – I increased Bottom Solid Layers to 5 for roughly the first 10mm using a height range modifier. Doing this everywhere would add a lot to the print time and the weight of the ornament.

Top Loop – I increased the Top and Bottom Solid Layers to 6 and the perimeters to 2 for the knob and loop at the top (100.25mm – 117mm).

Speed – I print at significantly slower than my printer is capable of. The model is detailed and has thin walls. This help to produce an smoother print with minimal gaps. It also puts less lateral stress on the ornament as it prints, making it less likely to be pulled off the build plate as it prints.