The original ceiling stand-off for my Ikea Husinge 5-spots Raillamp was too short.
I have added several heights, and tried them: They have a good tight fit.
For my white ceiling I chose natural transparent filament, but this is of course to you own choosing.
0.4mm Nozzle, 0.2mm Layer Height
www.123-3d.nl PLA 1.75mm
20% HoneyComb, and 5 layers wall, top and bottom.
I used a brim of 5 mm and my own special adhesive: a 10% solution of pine resin (as found in the woods) in orange oil. The latter will evaporate when using a heated bed (50°C) and leave a slightly sticky surface. This will crystallize during the cooldown, giving a crackling sound.