I would like to participate in the Instructable Community and I'm all in to sharing. I work as a 3D-designer and a teacher at The School of Design in Copenhagen. I created the rockets for fun in my sparetime and used the "BluePrint-drawing" in the Tintin story as my reference. It is therefore not a replica of the maquette you can buy in stores. I have not had any problems with the design or the print and the parts snap together nicely. The design of the 'blades' connecting the three 'feet' with the fuselage could be improved, but I generally like the small 'errors' in a 3D-print and only rarely spend much time sanding them with grid 80-120. When I do, I use a sprayprimer (Motip) to fill the cap between layers.
My setup is simple: Ultimaker Original (DIY kit) Nozzles: 0.4mm, Retraction: 4.5mm, Infill: 20-50%, Filament: GermanRepRapFoundation 2.9mm PLA, Temperature: 210 *C, PrintSpeed: 60 mm/sek, Layerheight: 0.125 mm (speed) 0.1 (accuracy). The rockets are printed with 0.125 mm.
Everything is modelled in Rhinoceros 5.0. The printtime of the lower part took about 6-7 hours (printed upside-down) with the settings above, you don't need any support, which might be surprising. The top takes 2 hours and each of the elements in the middle takes 1 hour (10x1 hour=10). The largest rocket (375 mm tall) took a total of 24 hours to design and print, and I printed all of the elements for the barrelshaped fuselage for the small model while I was still designing the lower part of the geometry, which I then printed overnight. The smallest model (190 mm tall) can be printed and fully assembled in about 6-7 hours, making it a nice school project, if you have a FabLab or similar :-)
The following images is from an earlier version using only two parts and manually created support for the lower part. I found out the support was not needed because one of them broke off, - and I decided to complete the print.