I've been looking at the virtual tour of the SERGEANT LEWIS. It's an interesting boat that wasn't built according to the plans. While the mainstrength bulkhead is exactly in the same place as in the 37, in the original plans it is intended to be one frame aft, creating a large aft cabin aft of the companionway
, with the galley
and sterncastle immediately aft. I suppose John Marples would be the best person to comment on the engineering aspect of that modification. It makes me wonder what other mods the owner/builder decided to perform. A number of boats were modified without the designer's consultation (including my own) but many didn't turn out as hoped by the builder
. It's trick to do if you don't have the design and building background.
The boat also appears to have some pretty beefy (heavy) components that have no structural reason for the weight. For example, the support of the sterncastle table with that massive grid structure, the heavy storage
locker doors, and a few other things. Weight creeps up on these boats, and it reduces the performance and payload (how much peanut butter you can carry).
If I'm correct, HAIKU is the product of Bob and Cindy Perkins
, originally from Los Angeles, then later moved to Oahu
where they ran a boat yard. Excellent builders, they built a 37 foot Searunner, one of the first using epoxy
resin in LA. They even crafted an oven
to cure the resin more efficiently.
In the interests of full disclosure, my modification involved how the sterncastle and aft wing decks got built. I was working as an ironworker, at the time, to make the money
needed for an effort of this magnitude. As a foreman, I had learned a great deal about structural design, and specifically, how extended decks could be built using walls and decks to transfer loads and create additional stiffness. There was a very active Searunner community which shared problems and solutions for all sizes of these boats. The little wing deck
running alongside the sterncastle was a problem since it had no support for any vertical loads, other than the thickness of the plywood
. Many were reporting cracks at the deck
to sterncastle wall joint. Also, in the 40, the design had a "hump" in the crown of the aftermost bulkhead, which held the sterncastle "window", that characteristically neat feature of the Searunners. It was not as graceful as that of the 37 or the smaller boats, because the boat's hull was narrower at that point than the 37. I came up with the idea to construct what is called a "T-beam". By building the wing decks 18" wide, instead of the 10" designed, I could then place a 2X2 stringer on top of the deck, using the outboard
side of it as the support for the new sterncastle wall. After the walls were constructed, I placed a temporary column support under the ridge beam of the sterncastle "roof", then jacked it up an inch or so with a hydraulic jack. Two layers of 1/4" ply, with athwartship "ribs" of Gougeon Brothers graphite bands were then epoxied and nailed to the top of the sterncastle walls. After 24 hours of curing, I removed the support column and went for a walk on the wing decks. They were rock solid, transferring my 250 pound bulk loading to the walls, then across the cabintop to the other side's T-beam. It also allowed me to reduce the curve at the top of the sterncastle, and with the added spaces port and starboard, include two oval ports
and a slender top port for stained glass panels
. Here's a couple shots that show the effect on the space. Note how far the cantilevered decks project
from the hullside and the sterncastle.