This is the Starfleet Insignia from the original TV series Star Trek ("TOS").  I modeled it from the tv series images of the Starfleet insignia.  

Some notes about this model:

1.  The model is optimized for printing as 2 separate pieces.
2.  It is a very tight fit for the 2 parts so that glue is not necessary.  
   1. If you want to make fitting the parts together easier (and use glue) then I recommend either:
      1.  increasing the size of the gold piece by 1% or 
      2.  decreasing the size of the black part by 1%