I'm not sure what you're trying to do with the two different cylinders but you're only subtracting the small red one from the larger one, rather than the logo itself. To 'punch a hole' you need to subtract the cylinder from the keychain like this: difference() { *logo stuff goes here* cylinder(*dimensions of 'hole' to subtract from your keychain*); } If you want to make a more complex hole shape then you can just keep subtracting more shapes. By the way, you will need to make the cylinder a smidge taller than the keychain and nudge it downwards by half a smidge (in the z-direction) so that it fully intersects the logo above and below. Also, $fn=100 is likely way above the resolution of your printer for creating holes 7mm diameter holes. HTH raymondpijpers wrote > [...] > > I found the difference() option and used two cylinders in this, but they > are not actually creating a hole in my logo. > > [...] <http://forum.openscad.org/file/n13469/Screenshot_-_07-Aug-15_%2C_10_33_30.png> -- View this message in context: http://forum.openscad.org/Cylinder-won-t-puncture-tp13469p13470.html Sent from the OpenSCAD mailing list archive at Nabble.com.