I was walking down the beach at Dead Boat Cove, not its real name just my appellation, the locals call it Dogpatch, when I noticed this Wharram design catamaran beached for work on the hull. The owner, Tom Hembroff, hauls her up every two or three years for bottom painting etc. Her name is Piggy, reasons not provided.
I noticed that he had removed the rudder hardware and was epoxying a 2x2 strip with a series of holes in it to the transoms. My noisiness, I tried to write journalistic instinct but it wouldn't come out, took over and I went over to see what was up.
Tom said that he was replacing the rudder hardware with something he had found on the Wharram web site, a lashing. I should have asked where on the site because I couldn't find it.
However, this simple idea will be perfect for rudders for the type of small boat that most of us build.
Essentially the pintles and gudgeons are replaced by a continuous figure eight lashing passing through the rudderpost and through a similar piece on the transom. On the big Wharram rudders there are several lashings.
But on a PDR, for example, one or two would suffice.
The beauty of this method, as Tom explained it, was that there is no chafe on the lashings, the top end could be epoxied into the hole and the bottom end made fast so that tightening could be done at any time. He was still pondering how to make the free end fast, see the last paragraph of this article, when I spoke with him. He did say that as far as he could tell once pulled taut the lashing didn't seem to move even with movement of the rudder.
If you were to combine this method with the Cary hinge you have an easy to remove rudder mounting with an easy to replace hinge mechanism.
Illustration 1: Cary Hinge as drawn by Jim Michalak.
The plan - rubbish the gudgeons and pintles, home, but not well, made, installed on my new PDR in favour of the Wharram lashing but without the Cary hinge. If you use a stopper knot with a loop as the start point and then take the end of the lashing back up to the loop you can tie the end off and secure the rudder.
I thought two sets of lashings as shown in the drawing above should do the trick.
I started with the existing rudder stock and a piece of 11/2x11/2.
Marking them up I drilled five ¼ holes a ½ inch a part. I then tapered the holes using a grinding stone in the drill press,
This not only tapers the hole but heat hardens the wood around the opening.
I then chamfered the mating sides on the table saw using a gadget I made up to prevent kick back.
The chamfer on both the rudder stock and the transom piece was then rounded with a belt sander. The transom piece was attached using two bronze bolts, which I saved from a previous rebuild project 20 years ago,
(my wife claims that I'm a hoarder, I deny the allegation) and a 3 inch ceramic coated deck screw into the skeg to secure the lower end.
The holes are actually 5/16ths to take ¼ inch lashing line.
Lashing went fairly easily but tightening the lashing was a prolonged process so I decided that next time I would a) use a Cary hinge type of set up and b) create a small hook tool to pull the lashing taut.
The end result looks pretty good and you have full 180 swing on the rudder without any binding or hang-ups, unlike the home built pintles and gudgeons.
The wire you can see hanging down in the left hand picture is used to secure the wing nut that holds the actual rudder on.
Which brings me to another matter, weighting the rudder. If you are lucky enough, as I am, to live on the coast near actual fishermen you have access to a chandlery where you can walk around and handle all sorts of non-yachting sailor stuff and because it's for fishermen not yachtsmen it's plain, sturdy and cheap(ish).
That's where I found the weights for my rudder, zincs. One on each side, through bolted. These zincs are nicely shaped to glide through the water with little resistance and they're much cheaper than lead.
Another piece of handy gear is the lids from plastic tubs, Gatorade cans etc. Hang on to them they make great bearings and they're way cheaper that CDs.
Yes that is a Harken block you can see in the lower right. No, I did not buy it. A fellow was cleaning out his garage and gave them to our search and rescue group but since you can't use yacht blocks for slinging people over a cliff I volunteered to give them a good home where they would be appreciated and loved. Kuai Le now has a masthead block that is a quarter of the weight of the previous one and has ball bearings too.
While I'm at it yet another handy item is plumbers copper strip, you know the stuff with holes in it every half inch or so, it can be used to all sorts of things.
Securing the ends of various lines for instance. It's not cheap but it's very useful. I had half a roll left over from a plumbing job in 1999. I am not a hoarder I just keep useful stuff, in the shop, in the dark, where nobody can see it and complain.
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