This is our design for 3D printable bumpers for an iPhone 6 or 6S Plus. The bumpers print and then immediately fit straight onto your phone straight off the bed. They are held on via friction fit. This is more than adequate to stay attached to your phone but also provides a quick way of removing the bumpers when needed. The bumpers offer a great amount of protection and look good as well.
NOTE: using the scaling feature of your slicer to decide how tight you want the bumpers to be. Keep at 100% scale if you want a loose fit or if you are printing with ABS. Scale to 97-99% for a tighter fit especially if you're printing with PLA. We found that the bumpers print best if you orientate the print so that the flat bottom/top sits flat on the build bed. We don't recommend printing the bumpers on their side.
We printed out bumpers in our own Blue ABS filament which is available here: http://www.3dexfilament.co.uk/product.php?id=14 We used a layer height of 0.2mm and an infill of 20%, however, it doesn't matter what settings you use as this design will yield good results regardless of the printer settings.
Please check out our website for more free downloadable designs and all of your filament needs:
Print time: 15mins
Layer height: Any (we used 0.2mm)
Speed: Lower the better (but we used 100mm/s)