B-DNA surface with base pair

This is an idealized B-form DNA duplex surface representation with a G-C base pair exposed. This helps illustrate the major and minor grooves, and helps to visualize how the nucleobases are involved in stacking within the duplex.

Files need to be scaled. Pictures are versions printed at 400%. Orientation will depend largely on your printer and what you can get away with for overhang angles. Certainly needs supports.

To put the base pair in it is easiest to clip the protruding cylinders from the sugar on one side just a bit and stick that side in second.