Flutterby™! : Wooden boat challenge 2009-04-08 13:37:16.89438+00

Wooden boat challenge

2009-04-08 13:37:16.89438+00 by Dan Lyke 5 comments

Went to the latest meeting of the Sonoma County Woodworker Association, this meeting was hosted by Craig Collins at West County Design, and he showed us around his showroom (nice furniture, also some interesting concrete surfaces from Bohemian Stoneworks), and then around his shop and some of his current challenges, including a set of (14?) chairs, with some good insight into his design and development process, and a walnut table with some fairly complex joinery in the curved legs. Definitely worth a visit if you're out near Valley Ford, and I need to just get to every one of these meetings because the two I've been to so far have had great presentations, and there's always good discussion.

Craig also mentioned (raved about) the Bodega Bay Fishermen's Festival Wooden Boat Challenge, and this seems like one of those things that simply must be done. Teams of 4 people, 2 sheets of 3/8"x4'x8' CDX, 2 2"x2"s, a handful of 1x2s, a box of deck screws, a bag of nails, ductape, caulk, rope, a sheet of plastic, and 3 hours. Only power tool allowed is a drill/screwdriver, which would make things more difficult for my shop, but I think this could be justification for replacing the cross-cut saw I destroyed when I didn't realize there was a layer of concrete under the tile counter top in the kitchen that I was reworking...

So I need to find 3 other people in my area interested in this sort of silliness. Apparently at race time it ends up bifurcated into two groups, the square ended ones (ie: folks who are happy to get their "boats" to float) and the pointy ones, and one of the square ended ones won this year because they start first (which means passing difficulties) and have an abbreviated course. Craig commented that, once you got the boat to float, a good portion of the competition was on the strength of your propulsion. Without actually having seen how the field lays out, seems like a time to take advantage of that "square root of the waterline" thing, an open kayak or C2, 16 feet long with minimal rocker, using the 2"x2"s for paddle shafts seems like the thing.

I witnessed one of these glorious debacles in Sturgeon Bay Wisconsin. I think rather than waterline the important criteria are buoyancy, stability, and integrity. I didn't see hull speed limiting any of the vessels. A common failure mode was loss of stability and buoyancy at the turning mark.

I think I'd look to traditional dories. 2 sides, 1 bottom, a tiny transom and one thwart. The curves are easily made with a spline and a few marks. Of course I would probably also fail miserably for the lack of a scarf joint. Don't be tempted to downsize to fit an 8' panel. It almost works but depending on your mass it is not stable. Small people only in a one sheeter.

I was thinking the scarf joint could be taken care of by using one of those 1x2s to back up the joint in general: Butt joint the plywood, slap the 1x2 on the interior side.. And it sounds like there are two classes of entrants (thus the two different courses), Craig was saying that the boat his team completed last year was actually almost good enough to finish and use in place.

I haven't cut large curves (intentionally) with a hand saw, but I was thinking doing something like a dory without the transom, but in a more canoe sort of size. A flat bottom on a narrow boat will make it fairly "edgy", so it'd be nice to split that bottom, but I don't know how to make that particular joint quickly. The other thing I was pondering was going more "rowing shell" sort of shape, except with outriggers on the oar pivots (extra build time, but these could just be little floats), but I'd be wary of building a system in which the rower could exert more force than a 2x2 fir paddle shaft could withstand.

Other hint from last night: Any cuts that can be made through both pieces of plywood at the same time are better.

We have a group up here that builds wooden-framed boats using (usually treated canvas, but sometimes) a blue tarp for the hull. How big is that sheet of plastic?

9x10, so it'd work for a small hull, but probably be more useful as a sail (if there's wind).

I was playing around with a 4x8 rectangle in AutoCAD this afternoon and found a number of designs that would probably work well. Then I remembered the cuts would all be by hand. That complicates the shaping of the 1x2s for someone with my limited talents with a hand saw.