Maker 12.5 -A vintage sailboat with a Maker's twist

thingiverse

I was browsing through Thingiverse and stumbled upon the STEAM challenges, particularly #makeitfloat. After just a few minutes of reading about the contest, I knew exactly what I wanted to design and print and how to integrate the STEAM requirements! I love the romance of wooden sailboats. They are a beautiful fusion of art and science. Each one is crafted by a maker's hands, its design influenced by the scientific interaction of wind, wood, and water. It's so cool that a mathematically and aesthetically pleasing shape are the same thing! There is a small sailboat I've always wanted to build for myself - the Herreshoff 12 1/2-footer, designed by "The Wizard of Bristol" N.G. Herreshoff in 1914. Over time, this boat has become an archetype in the field of small wooden sailboat designs. It inspired Joel White, a modern naval designer, to develop a version with a retractable centerboard, the Haven 12 1/2. Mr. White's willingness to combine historic and modern design inspired a new generation of 12 1/2 makers to build them using modern techniques and materials while staying true to Herreshoff's charming daysailer lines. Thanks to inspiration from the #makeitfloat challenge, I decided to put a Maker's twist on history using modern desktop 3D design and printing methods. Working from found images only, I began reconstructing the Mini-me version of the Haven in my 3D design software. Not surprisingly, I had to revise parts and design details to accommodate the size, printability, and purpose for which my design was intended - a scale model, not a sailboat for four adults. Once the virtual model was complete, I added the Makerbot logo as a finishing touch, swapped the fraction for a decimal, and christened this vessel, Maker 12.5 in tribute to its heritage. A bit of old, a splash of new, and a sprinkle of Makerdust! In addition, there's a nautical science aspect using coinage that can be demonstrated with this model using the 12 1/2 foot load waterline length (LWL) measurement that gives the craft half its name. I've split this model at the LWL to make the line obvious and for ease of printing. The waterline is often indicated by a stripe or color change down the broad side of the hull, serving as a visual reference to the trim of the boat in the water. A naval architect computes the weight of the boat and its gear, passengers, and cargo and integrates that information into the hull design to generate the LWL line. Although a waterline can be any line where the hull intersects the water, the LWL is a special line that indicates where the boat will float before it starts to use up its reserve buoyancy. It can also show if the boat has its weight distributed properly fore and aft as well as port and starboard. As the boat sinks in, the hull displaces the water according to the volume of its hull below the waterline. The term displacement, in this instance, refers to the weight of the water shoved out of the way by the hull. By changing the amount and distribution of the weight around the design, you can find the answer to this question: How many quarters does it take to ballast this design at the LWL as designed by the naval architect? I theorized that it wouldn't take much weight, but I was concerned that it might not float at all! Nonetheless, I started filling the sink for testing. I did have some small hurdles to deal with that didn't become evident until testing. The main issue was knowing that due to the sparse infill, this design wasn't watertight and would gradually flood with water, affecting the test. I solved that issue by applying a thin layer of plastic wrap over the hull. The second was that the model was biased toward one side due to the angle of the sail rig, so I had to compensate by offsetting the ballast to the side. Once those problems were worked out, I started loading quarters and arranging them to find the answer to my question for the #makeitfloat challenge. So, how did it turn out? Check the pictures above for the results. I had already tinted the hull, so I used a thin layer of plastic wrap on it to keep the color from bleeding while it was in the water. The first test result pic shows the Maker 12.5 with the quarters in place, and the second shows the results at the waterline when ballasted. More info is on the instructions page, and I also wrote an article for 3dprint.com about the process, giving Thingiverse a shout out: http://3dprint.com/81733/3d-printed-dailboat/.