March 26, 2008

Wayne’s latest design thoughts

As the project has been getting more active lately, Wayne & I are going to start meeting more on Wednesday’s. We had an interesting design discussion about some of his thoughts on spar construction, Personal Seasteads, and detachable spars. Highlights:

  • Our favorite initial business model is the “Personal Seastead” or “Sea RV” model (as opposed to aquaculture, or an offshore seastead). We like this for several reasons:
    • Coasteads are relatively small, both physically and financially (< $1M each, ideally starting at < $100K once we get some scale and have a factory in Mexico), so make a good starting point.
    • There are no offshore operational responsibilities, which would be challenging. At some point I’m willing to be a pioneer and go live on a crazy platform in the ocean, but I’d like to live/work in the cozy Bay Area for as long as possible. An offshore venture should wait until things are really solid.
    • Selling many small units to interested people has the potential to get broad involvement and seed the idea widely (compared to a few large units or a commercial operation).
    • It dovetails perfectly with Ephemerisle – if there are dozens or hundreds of personal seasteads out there, it makes it really easy to do periodic Ephemerisle festivals, where the seasteads are the base but boats can come join too. And those will be great for experimenting with temporary autonomy and building interest. Imagine if you could easily bring your house to Burning Man or Pennsic and whatever you built or created there easily came home with you. That would be so much better for integrating the movement into your life the rest of the year than having to set up and tear down temporary structures.
  • Both of us have been thinking about making spars in sections. That way our mold isn’t that big, and a single production facility can produce spars of many different lengths. Also a spar can be extended as a retrofit if needed. Wayne had some specific ideas about how to best connect the sections.
  • We’d also both been thinking about detachable spars. There is a basic design conundrum with the Sea RV model, in that ocean safety requires long spars, which means a really deep draft, which means it can’t dock at any normal pier. We need to solve this. The solution pretty clearly involves having the top platform and the spar be separate pieces, with the platform able to float on its own.
    • We had an earlier design which was that the safety hull was a donut shape, which the spar went through. In ocean mode, the hull is bolted to the top of the spar. In shore mode, you sink down until the safety hull is on the water, make the spar neutrally buoyant, unbolt it, make the spar positively buoyant, and move the spar up until the safety hull is sitting on the lower hull (or close to the bottom of the spar if there is no lower hull). Then re-bolt. With the safety hull on the water, the boat will be very stable because it has a strong righting force, so it’s not a big deal to have this huge pillar sticking up in the air.
    • Wayne’s latest design thoughts are to have the top platform essentially be a catamaran shape, with the spar fitting between the two hulls. That way it can slide out and the two can separate. The spar can be left offshore or towed (it would ride much higher in the water after removing the platform). The platform then becomes basically a boat, with very little draft.
    • In either case, Wayne suggests building the platform/safety hull out of light materials (wood and fiberglass, or possibly steel) rather than ferrocement. Basically, the less weight there is on top, the less ballast we need, the smaller the spar can be, etc, there are all kinds of materials savings.
    • Wayne had the clever idea that we could have two spars for Baystead: one that allows us to dock at SF Bay piers (at most 30-40′ draft), and a longer ocean-going spar that we mount when we are going offshore. It would not be very practical for the general Sea RV to come with two spars (or necessary – we need to be demoing the ocean-going capability to people who come see Baystead at the pier, whereas someone who has one recreationally should be fine with docking the spar and hull separately). But for Baystead it’s perfect! (Although note that if the sliding spar design works, one spar might do for both, the platform could be mounted at different heights depending on conditions)
  • We both agree that there should be a huge central room, with lots of natural light and a panoramic 360° view.

That should be plenty to chew on for now. Sorry if any of this is confusing due to lack of pictures.