Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:1468939.
I love building cigar box guitars...but have never been able to make a nut I've been happy with. So I figured why not try 3D printing one :)
Seems to work better than anything I've managed to carve out of hardwood, bone or plastic by hand! Maybe I should try printing up a better bridge next...
String grooves are sized to fit the A/D/G strings from a set of standard 6 string guitar strings and are spaced to work with a picture hanger bracket I use as a tailpiece. The openscad source is included so it should be relatively easy to adjust the size and positioning of the string grooves to work with other setups.
I left the nut a little tall which gives somewhat higher action on the strings than I prefer. But it's a lot easier to sand it down a bit to get the action just right than to make it taller after printing!