Smithy's Southern Cross

prusaprinters

<h4>Summary</h4><p>The Southern Cross was made famous by Australia's Charles Kingsford Smith's record-breaking flights. (First non-stop crossing of the Australian mainland, Trans-Pacific flight, England to Australia air race).<a href="https://en.wikipedia.org/wiki/Southern_Cross_(aircraft)">Wikipedia</a></p><p>The aircraft is now preserved in a glass-walled memorial at Brisbane airport. In around 1966, my family visited the memorial. I'm not sure how it worked, but we had a private tour inside the aircraft. It left a lasting impression on me. How could such a dangerous journey be made in something so primitive? I remember the pilot's seat particularly, like a wicker chair I'd expect to see at grandma's house.</p><p>The moon landing was only three years away; I was a child of the space age. Then I saw primitive technology, but I now see parallels. Both were long, dangerous pioneering journeys whose success led to changes in what humanity imagined possible. (We can fly around the world and to the moon). Both used new technologies untested over great distances.</p><p>Though the trip by an Aussie in a rebuilt second-hand aircraft led pretty quickly to transnational airline routes and international travel, on the other hand, it took 400,000 Americans to build Apollo. Yet, they haven't even managed a second go at it, let alone have tourists on mars.</p><h4>Print Settings</h4><ul><li>Printer brand: <a href="https://www.amazon.com/3D-Printer-Prusa/s?k=3D+Printer+Prusa&amp;linkCode=ll2&amp;tag=tv-nothing-20&amp;linkId=28c787aef7c5a20cf2004b821dd161bf&amp;language=en_US&amp;ref_=as_li_ss_tl">Prusa</a></li><li>Printer: <a href="https://www.amazon.com/3D-Printer-Prusa/s?k=3D+Printer+Prusa&amp;linkCode=ll2&amp;tag=tv-nothing-20&amp;linkId=28c787aef7c5a20cf2004b821dd161bf&amp;language=en_US&amp;ref_=as_li_ss_tl">I3 MK3S</a></li><li>Rafts: No</li><li>Supports: No</li><li>Resolution: .2mm</li><li>Infill: 15%</li><li>Filament colour: Blue</li><li>Filament material: PLA</li></ul><h4>Post Printing</h4><p>I've tried to make construction as tool-free as possible, but FDM is not great with fine detail.</p><p>The model uses 'friction fit' to join parts. However, as most parts are tiny minor differences in size, like those affected by printer tuning, may make parts too loose or too tight.</p><p>I've erred a little on the side of too large, so you may have to file or sand some parts. On the other hand, every joint is designed with a small tolerance, so you may have to glue others.</p><h4>Designing</h4><p>I was interested in the process of designing a 'kit card', that is, creating a kit of essentially 2D objects that the user could assemble to make a 3D one. The project also meant experimenting with press-fit joints and imitating a sprue tree.</p><p>The difficulty was with the finer details. Many things that give the aircraft recognisability or character wouldn't print reliably at scale. (1:86). I had to combine, enlarge, simplify or omit. However, I found it difficult to predict what it would look like, so I had to iterate. Easy with small parts because they print quickly.</p><p>A related issue was fit. I found that small openings need larger than expected tolerances; trial and error was again the only method.</p>