Another couple of Covid Lockdowns (the fourth and fifth!), and another 3D project! This time it was off to the moon with a model of the Apollo Saturn V.
Rather than designing my own rocket from scratch, I hunted on the web for a good quality model in .stl format. There are many Apollo Saturn models available, but few match the quality and attention to detail of one I found on Thingiverse, created by Thingiverse contributor Farscape1.
The project files include the components for the rocket and launch tower in amazing detail. As the design files were created with the intention to be printed as a 1/60 scale model, the finished 3D print would be just over 1.8m (6′) tall for the rocket, and about 2.3m (7.5′) tall for the launch tower!
This means the print time would have taken… um, too long! Therefore, I decided to shrink the Apollo/Saturn model to about 60% of the designed size to a more manageable 1/100 scale! Maybe I’ll tackle the launch tower one day, but for the moment, the rocket is enough!
Farscape1’s full size 3D print of the rocket and tower took about 21kg of PLA plastic and two 3D printers about 2000 hours to complete! Mine was more manageable by not printing all the small detailed parts or launch tower. Printing the rocket at 60% of the original file size and excluding most of the internal pieces took 900g of PLA plastic… don’t know about the time exactly, but it took many days!
Along with the .stl files, Farscape1 provided an eDrawings Assembly File (.easm format); a 3D CAD file produced from his original design files. Viewing the .easm file without a program like Solidworks, requires an eDrawings viewer program. I downloaded Solidworks’ free eDrawing viewer for Mac (OSX High Sierra), but it wouldn’t load the Apollo/Saturn/Launch Tower file (or any .easm file for that matter!) I did get the Windows version to work (running on Mac under Parallels and Windows 10), and it also works on Mac under OSX Mojave.
Click all images below for larger views.
eDrawings view of the overall design.
Using eDrawings, the rocket ‘stack’ can be separated and the components rotated in 3D space to get a good view of how the printed parts fit together.
Below: Three of the five F1 engines for stage 1. Engine on left still has printing support material to be removed. The original .stl files were very detailed and complex, comprising many intricate parts for each engine. I loaded the main parts into Lightwave and produced simplified .stl engines.
F1 engine cluster Superglued into place on the bottom of the 1st Stage heat shield. Each engine produced around 1.5 million lbs of thrust, for a total of almost 7.5 million for the whole cluster. Apollo 11 was 363′ (110.6m) tall, and weighed 6.5 million lb (2,900 tonnes; the weight of 11 fully laden A380 Airbuses!). Its five F1 engines provided enough thrust to lift the whole Apollo/Saturn stack from the launch pad to an altitude of about 42 miles (67km), and accelerate it to 7.500 feet per second (2,300 metres per second; 6.7 Mach) during the 168 second burn! For comparison, the most powerful jet engines ever made (currently the General Electric GE9X turbofan engines used on Boeing’s latest 777X aircraft), only produce 110,000 – 134,300 lb force each!
The original design had the black and white pieces as separate .stl 3D print files. But I found that it was too difficult to glue the pieces together, so decided to print everything in white plastic and paint on the black after assembling each section. This meant loading many individual part .stl models into Lightwave and producing simplified, combined larger .stl pieces.
Painting Stage 1 – lots of masking tape was used! The triangular piece is an engine cowl, and the cylindrical piece at bottom looking like a cotton reel, is the Apollo Service Module. Most of the painting was from a spray can, but tidying up the edges was done with a small brush.
Stage 1 tank upper dome spray painted. Paper decals applied.