This thing was originally a small part of a bigger project I made (See http://www.thingiverse.com/thing:290064 )... However, I decided to upload it as its own thing when I realized it can easily be imported and added to any design or thing anyone wants to make that requires fastening of separate parts with a nut and screw...

The part is cool in that the nut is permanently confined within any "thing" you add it to - it will never fall out - yet still prints as one piece without ever fusing to the shell surrounding it... It is designed in a way that allows it to spin freely while never separating from the shell or bigger part that encompasses it. With the spinner, I also provided a hollowed out base containing a perfectly sized and scaled screw. Located in the geometrical center of the base, the screw flawlessly slips into the nut with little to no aligning or effort - all while still maintaining a very tight grip...

It's good to print as is... But it's best used as a component to import and add to bigger parts.... The two pieces are together, so scaling to any desired size should work with very little tinkering... It prints perfectly as one piece and I have yet to have a miss print... I tried to minimize the need for the printer to add supports, yet it still does and a few little slivers of PLA chill between the nut and shell when the print is finished- if this is bothersome, like it is for me - just get needlenose pliers or tweezers and pluck those little bastards out like unwanted nose hairs.