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by Dan Rogers – Diamond Lake, Washington - USA

In my earlier days with cabin boats in the 20 to 25 foot range, I came to believe rounding up in a gust was not only inevitable - it was a desirable safety device.  Granted, that was before I understood much about sail trim, proactive steering, and all that stuff experienced sailors do and know instinctively.  It was also in boats that were more or less designed and marketed to live most of the time on a trailer.   Those boats from now-long-ago, possessed underwater appendages designed more for ease of launch and retrieval than actual sailing.  Shallow, transom hung rudders; requiring a bit of acrobatics to lower and install.  And, only installed after the boat was safely launched.  Only retrieved before going back on the trailer.

Now, after additional decades at the helm of a series of deep keel, inboard spade rudder, go-fast rigged “cruiser-racers,” I find myself, once again, as owner-skipper-custodian-shipmate of a pudgy, shallow draft, ramp-launchable 16’ pocket cruiser.

The very first time I launched Lady Bug, I managed to shear off the bolt holding one of the pintles on a 5-foot tall solid mahogany rudder.  I simply hit the rudder blade on the launch ramp, when the hull was inclined stern down.  Along the intervening years, I’ve managed to ground that rudder on just about any kind of bottom available, from solid rock to squishy mud.  Sometimes, it was quite difficult to get those pintles disengaged from those gudgeons when under side-loading generated by the collision of a still-trying-to-move 1500 pound hull, and an ain’t ever gonna’ move ocean bottom.

Anyhow, I went searching for a way to have the benefits of a kick up rudder without the inherent weakness, drag inducing pivot joint, and the often wobbly nature of such a thing.  That brought me back to studying on why some shallow draft, relatively short and fat sailboats tend to carry inordinate high levels of weather helm.  And, why their rudders seem to stall at the drop of a hat.

Many of the larger (externally ballasted keel) boats in my past simply heeled over a bit, and squirted ahead in the gusts.  None of this weather cocking behavior for them. Simply put, those boats had easy runs and slim prismatics.  My current boat, Lady Bug, is just plain short and fat.  The keel is short in both chord and span.  The rudder hangs lower than is healthy, already.  And, if you thought that little spit kit rounded up with the original, quite conservative, rig.  Guess what happens now that I have replaced all that with much, much taller beach cat mast and full battened main.  We simply had to have more grip on the water.

First off, I dropped the rudder about 6 inches even deeper in the water.  Then, I rocked the toe of the rudder blade forward to increase the balanced tab effect of projected area forward of the pivot axis.  And, presto!  We have about the closest thing to a neutral helm as can be gotten from a steam iron shaped waterline.  But, there’s a serious problem that comes with the improved performance.  

I don’t think I’ve ever read a technical discussion of such a thing.  But.  It often seems like the rig is “sailing away” from the hull.  And, I do have a germ of insight.  The rig in question did come from a Hobie 14.  A boat designed to sail at speeds well above what we consider “hull speed” for a 14 footer.  My more-or-less affectionate nickname for this boat is “Turbo-Turtle.”  She has a big heart, and really short legs.  And, that’s probably about where this experiment will reach a conclusion.  However, there is one ancillary discovery that I’m going to attempt to share.  By trial and error, accident, and insight I came to a sort of hybrid arrangement that really doesn’t seem to get tried out much.  Maybe, not at all.

To get a rudder to kick up, there must be some sort of pivot.  That’s a given.  The Hobie castings, the Laser fabrication, are examples of really elegant arrangements.  However, these arrangements are for light weight, fast boats that can almost sail on a dew drop.  What about a small keel boat that needs an almost-four foot draft?  What about a boat that isn’t ever going to be moving at more than 5 knots?  The side loading on that rudder head is going to be way beyond the original design limits (for the Laser/Hobie, etc.)  The high aspect beach boat rudders will stall long before such a boat can be brought about.  I know this, because I’ve tried it.  So, this is my iddy bitty “discovery.”

I simply pivoted a relatively deep, relatively broad foil from the top.  What I got was essentially what the Vikings got with their steering oars.  The majority of the weather helm-induced side loading goes directly from the water to the helmsman’s hand.  No pintles and gudgeons to rattle and twist loose.  No bulky pivoting joint at or below the waterline.

Just about all the load is transmitted through a stout “bicycle fork” kind of thing at the aft end of the tiller.

The rudder blade needs to have something to keep it vertical and on the center line.
My particular home brew contraptions have morphed from the complex to the bizarre.  This is an earlier version that was pretty complicated and the tiller was too short.  But even here, with my friend, Roger, sailing with the main over trimmed in 30+ knot gusts, the little girl is going where she’s looking.  And, that’s pretty close to success.
But, this latest one in a long series (certainly, not the last) is a pretty simple aluminum weldment with Delrin and nylon bearing shaft (these pictures still show the “original” ½’ ss bolts and nylox nuts) and bushings here and there.

The rudder tilts up at about a 45 degree angle for launch and recovery from a non-extending trailer.  I don’t approve of launching boats with the launcher wading around and getting his/her shoes wet.  So, the result here is to launch Lady Bug with the tow vehicle’s tires uphill from the water.  She rolls from a position where the keel is nearly dry, to floating, in a controlled fashion.  And, except for once or twice, the rudder goes along for the ride without complaint.

Oh yeah.  And this particular 16 foot hermaphrodite-contraption has a one fathom long tiller, currently.  Yep.  Power steering. 

I wonder what I’m gonna’ try next?

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