Unsatisfied with the existing options out there, I decided to design my own variant of the legendary space shuttle in launch configuration (full stack). It roughly matches the dimensions of the vehicle at 1:285 scale, but includes several tweaks to make it printable on a Prusa Mk3 (or any FDM with similar build volume) with no supports. It includes cutouts for attaching magnets to connect the stages together, and two internal holes to help align the two halves of the orbiter for gluing.
Print the fuel tank and the (2x) boosters in the default (vertical) orientation with support disabled. Print the front and back halves of the orbiter with the separating slice on the bottom. Optionally using two 3x35mm rods for alignment, super glue the two halves of the orbiter together.
To utilize magnetic attachment, you'll need super glue and the following magnets:
The author marked this model as their own original creation.