A Photo & Discussion Forum for Wharram Design Enthusiasts

lashing for rudder question

I have a 25 foot umiak trimaran. This funny boat has a steering oar. It is 11 feet long and made from fir heart wood so is very heavy. I trailer this boat about and so need to get the oar out of the way during transit. So i made an attachment point for the oar that uses the figure eight form of 'hinge'. It worked remarkably well on today's sail (crab claw fully up). But i made the wood in the attachment piece parted since i made it a bit too narrow for the load of that heavy oar and the forces exerted as the trimaran takes the wind, but not a real problem. I will just make it a bit more robust. The larger question is this....i used dynex dux line, but because it cannot stretch, it was impossible for me to get the oar snugged in tightly. How do you put tension on these lashings for the rudder and then tie on a stop knot? Does that make any sense? I know i am dealing with something way smaller, but the tension issue is still a problem, i think. At the moment i am contemplating using a softer line that has some stretch, and attempting to stretch it into place before somehow knotting it.
thanks.

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Permalink Reply by Cooper Dan on February 25, 2014 at 8:54pm

Hi Cliff
There are couple of images on the link below on a homemade tool that we use to tighten the lashings.
Two person job, the person on the other side is using a soft spile, piece of wood, to hold the lashing tight in place while the next section is about to be made tight.
Worked from top down, not able to move or wiggle the rudder so this was the only way could make lashings tight, and they are very tight :)
Overhand knot, then another behind the first.

http://wharrambuilders.ning.com/photo/album/show?id=2195841%3AAlbum...