Slipper has made a bit of progress toward completion lately. The scraps of cheap lauan underlayment I used are falling apart where they lie on the dirt, so I thought I’d better get some paint on the hulls before they fall apart too.
I think the hulls are modestly graceful, and I might even leave a bit of varnished wood for an accent. I like the sheer– not very pronounced but somewhat handsome anyway.
Here’s a shot from behind:
In my last post, I mentioned that my first approach to lashing on the beams didn’t work out. I developed another that seems to work a lot better.
The idea came to me because of a casual conversation I had with our excellent neighbor, Ed Lussier, a retired Air Force Lt. Colonel. Ed’s a smart guy who’s helped me out in a lot of ways. He was telling me about a bar bet with which he’d won a drink or two: you claim that you can break a stout piece of rope. When you find someone drunk enough to take the bet (I’m paraphrasing Ed here) you go outside and find a couple of sturdy objects and loop the rope between them. You tie loops in the rope until, by threading the loose end through loop after loop, you develop sufficient purchase to pop the rope. It’s sort of the same thing as a trucker’s hitch, but turned to evil purposes.
I didn’t want to pop the lashings, but I wanted to torque them down pretty well. So my new system involves a couple of lengths of 3/8″ Dacron three strand, with eyesplices in one end. A stopper knot secures these in the crossbeam, and then they wrap around the bulkhead reinforcing and back through the crossbeam. A length of slippery 5/16″ halyard is tied to one eyesplice and then is looped through both eyesplices, tightened, and then cleated off.
Here’s what it looks like on the other side:
Another problem with my first attempt was that the lashings wrapped tightly directly underneath the bulkhead framing, which gave the crossbeams tremendous leverage to stretch the lashings. I reinforced the bulkheads so that the lashing hole could be moved away from the crossbeams, giving a more advantageous force vector.
The lashings seem really tight now, but I guess I won’t know how they work until I get the boat out on the water. Maybe I’ll try out the boat just with paddles one day soon. If they work pretty hard, two folks can get Slider up to 3 knots in calm water. It’ll be interesting to see how fast two folks can paddle a much lighter Slipper.
on Aug 21st, 2009 at 8:51 pm
I like the use of I beams and I think the decision to go with rope lashings rather than pins was a good one. One my Wa’apa I have boxed beams that sit on the gunnels and are lashed to holes either side of the beams through the hull. Why I like your lashing idea is because you put one rope through the holes, which saves a lot of threading rope through the holes all the time. You just use a short rope to tension and tie off. In my view, I think a thinner tensioning rope would be better so you can make more turns and increase the physics. A shackle might reduce wear on the ropes. Looks good.
Mike
http://muckingaroundintheworkshop.blogspot.com/