A quick note: this post dates back to three weeks ago, but was unfortunately not published until now.
The goals of the fabrication team this semester are to make our sailboat manufacturing A+. The ultimate hope is that, when we show our boat, people will think that it was professionally made for thousands of dollars. Of course, the idea is not to actually spend thousands of dollars on manufacturing, but still have awesome quality and a good-looking boat. As a rule of thumb, things that look good function well, and that is what we want for our fabrication.
This concentration on manufacturing means LOTS of prototyping. The current approach is to make a male mold—basically cut a bullet shaped piece of solid boat out of foam—and then glue several smaller molds together to make the final shape. Then we cover this with carbon fiber/fiber glass, and carve pockets under deck to put in the guts, such as the electronics and sensors.
Preliminary fabricated hull
Carbon fiber pieces
It’s a little harder than it sounds to get this process efficient and fast. It involves figuring out how to cut the boat by properly working the CNC router,* and then you still have to get the pieces together, layer the foam in carbon fiber/fiberglass and get a good-looking finish. Obviously, this process is pretty difficult.
Right now, the fabrication subteam is focusing on smaller details as well as the final hull. For example, it’s really hard to make bows of boats. Generally, the nose of the boat comes to a point, and it is very difficult to put carbon fiber over a point and have it come out well. Thus, we are actually taking that piece entirely off and molding a solid polyurethane bow to the boat. Also, everything in boat needs to be fastened securely—the mast and keel can’t be moving around—and so we’ve been figuring out ideas for how to accomplish that. Currently, we are trying different approaches—for example, using woods and structural hard foams. We are also experimenting with everything on a small scale: we are making 1/3 scale boats that can be used to figure out the tech on a small scale allowing us to see how and if it works.
*A CNC router is a mill that is automatically actuated. This means that it moves the cutter in 3 dimensions and carves the material to get 3D shapes. This saves a lot of time that would otherwise be spent doing lots of sanding and extra work.