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hello again,I'm on the whiteoak river near bogue sound in N.C..................I have a heavy bungee for rudder damage control and it works like a champ,however, the river and sound are shallow here and the channels are very narrow. this restricts my sailing time to two or so hours on each side of high tide. the launch site is also shallow but I can motor in and  out if I'm careful. Is it possible to shorten the rudder or modify it with two shorter ones and have enough bite? Tacking every twenty feet or so in some places is not as much fun as you might think and makes for some slow going.............thanx................bruce W.

I'm not sure which boat you have, but a barn door style of rudder would reduce the draft considerably, though some pointing ability will likely be sacrificed. You'll want the same amount of area, possably a little more in the new rudder. Picture cutting the rudder at about half way down and attaching this piece to the trailing edge.

You could also provide a kickup function to this setup so in really shallow water, it'll bounce up, but still have fairly good steering.

Another option is the cassette style of rudder, where it's a bit like a daggerboard. When you hit bottom, you just raise it up a tad and continue on. These are more prone to damage, though the Austrian style helps to a great deal.

thanks for the input paul,I built a weekender last year.I'm putting in the reef points as you suggested.The rudder already kicks up and that has worked very well..............sometimes when the rudder is up a little,due to a strike, I'll leave it up a bit to navigate back to the deeper channel, but the pressure on the tiller is excessive and it seems to slow the boat down a lot..........when I'm motoring through some shallows with the rudder partially up,there is also a lot of pressure in the tiller............I think too much pressure because I feel the tiller flexing and I've overbuilt the tiller a bit............I've made a few alterations from the plans but am really happy with the way it turned out.............just added a topping lift and each time I go out I find some other modifcation to make things easier..thanks for the replies,everyone has been most helpful..............................build pics at whiteoaksails.com.................................

The three rudders in the middle (lower most attachment) are barn doors. These are on a Weekender hull, also showing different keel profile configurations.

In most cases the barn door style of rudder should be no lower then the bottom of the keel. On a Weekender, with it's weird keel profile, the barn door will strike bottom and probably get damaged, because of this odd deadwood profile. One solution would be to make an extension to your deadwood assembly. This would simply be drawing a straight line from the lowest point under the bow, back to the transom. This would be similar to the top two images, though on these the forefoot is cut well back (a good idea too).

The net result will be the CLP moves aft a bit, which will ease the pressure on the helm from a barn door. The barn door (or a kickup in the raised position) exerts a lot more leverage over the tiller, which is why the helm pressure goes way up. This is because a spade type of rudder uses lift and angle of incidence to steer the boat, but a barn door style uses only angle of incidence (for the most part). Since the barn door's leverage point (center of area) is much father aft of the gudgeons then on a spade rudder, the leverage it has over the tiller is substantially increased (to the 4th power in fact!).

If you extend the underwater profile from the bulbous forefoot, straight aft to the transom, the added lateral area aft will help compensate for the additional pressure. If you couple this modification with a cut down forefoot (like shown) the boat will suddenly become more responsive to helm inputs and tacking will be easier. Since the keel will still be a long one, she'll still track like a freight train, but because of this additional area, she'll have greatly reduced leeward skid, further improving her abilities, particularly to windward. If you sailed with an unmodified Weekender, but you had the above changes, you'll get to windward better then they would, mostly because they'll be skidding to leeward about 15 degrees, compared to your 10 degrees. Over the course of just one mile, you'd be several hundreds yards to windward of the other boat, making more VOG closer to the next tack.

Lastly, with the keel extension, your lower gudgeon would be farther away from the upper one. This added leverage over the rudderhead will help with the force needed to crank over a barn door. In short, a barn door is a common and traditional way of making a shoal draft rudder. It's not as efficient as a spade style of rudder, but it doesn't bang into stuff either.



This is a design (above) by Jay Benford and shows a fine barn door rudder. Note the tiller reaches over the rudderhead and down to the aft end of the blade. This added arm provides additional leverage to the tiller and looks cool too.

paul, thank you for the assistance,once again you have given plenty of food for thought...................the fore foot trimming worries me a little because it seems indestructable now because of the clearance when I beach her or accidently run aground.............but I assume this is where a lot of the improved handling comes from.................................I am not knowledgable enough to understand the handling implications of each modification,let alone several combined.  what if I were to trim the foot as indicated and add a piece to the keel,say maybe three feet long tapering to the rear(I'm not sure how deep) to protect the new barn door rudder? Would the handling be better or worse?  Any way I do appreciate your thoughtfulness and to start my experimentation I'll take your initial advice and make a temporary rudder about half as deep and add some area to the aft of it and use the existing rudder box and allow it to pivot and see if she'll turn and hold a line...........bruce

When you approach a beach, the bottom slopes up toward the shore. If you're deeper in the forefoot then anyplace else, you run aground in knee deep water with the stern still floating. If the keel profile is shaped as I have shown in the top three sketches, the forefoot will hit bottom in much shallower water and most of it will contact the bottom at the same time, spreading the impact loads. You'll get out in ankle deep water (at the bow) rather then knee deep and the stern is still floating, but much more secure as the forward 1/3rd of the keel is resting comfortably on the bottom.

If fact, if you look at lots of shoal draft designs, you'll not find a single example of the bulbous forefoot profile these boats have. The only example I know of is a centuries old middle eastern design that dates back to the Egyptian Pharaohs. These boats had all the same handling attributes of a Weekender, slow in tacks, easily caught in stays, bow steering tendency in chop, etc.

Part of Weekender's handling issues are is the bulbous shape of the forefoot profile. We've long known (a couple hundred years now) about the benefit of reducing the depth of the forefoot. It's one of the reasons the original yacht "America" kicked the crap out of the British so many generations ago. The Brits still were into the "cod's head" mentality, which didn't prove out as we "colonialists" had shallower water and need flatter bellied boats, which also happened to be much faster and more maneuverable too.

To improve the handling further, you can install a "Brewer bite" in the aft portion of the deadwood. This makes the rudder work better in cleaner flow. The forth sketch down shows the modern version of this design element.

The last thing you want is to curl the deadwood assembly upward as seen in the stock profile. This causes all sorts of turbulence and is the very reason you'll never find another keel profile like these used on the Stevenson designs. If you look at Jay Benford's (big time NA of considerable note) little ketch, you'll note the lateral area is aft, progressively more so as you move along the LWL to the transom. This is the usual and normal way of handling lateral are in shoal draft craft. My sketches do precisely the same thing.

paul, I hate it when your right............................o k the fore foot is definitely coming off...............that will be easy enough to eyeball but the overall profile and dimensions are not that clear ..................Naturally I would like to get the best performance possible given the shallow conditions , but fear losing stability in rougher and windier conditions that sometime arise............also the deadwood attachment method is a little daunting....... WWPD  {whatwouldpauldo}..dimension specifics would convince me you're a god..............the best profile ,depth of keel at the rear and size and shape of the barn door rudder.........................my keel is 3 layers of select yellow pine glassed and thickened epoxied down about 2 to 3 inches down from the attachment point then 2 coats of unthickened epoxy and then paint over that.......................has held up great but still young..........duckworks pintles and gudgeons should be o k to use again?  feel free to raise your middle finger into the air at any point and I'll respectfully sail into the distance...................bruce

Bruce, your keel sounds well built and it's durability suggests such. Good job.

You will not loose any stability by cutting the keel and adding to the after end. In fact, you'll gain a slight decease in the roll moment (technical stuff for how fast she rolls from side to side). Weekender is a fairly stable little boat.

Yes, your DuckWroks hardware can be reused. That RaceLite stuff is well made. Send me an email and I'll send you some specs, with an address for the six pack delivery.

The process is fairly straight forward. Level the boat on the trailer, but using the known waterline and the trailer jack. One she's level fore and aft, then level her side to side with a bubble level on the bottom. You can deflate a tire for a quick lowering of one side (check the fore and aft level again, when you've done the side to side, as it'll probably change just a touch). Once it's level use a string, tacked to the lowest point of the keel (a few feet aft of the point of the bottom) and stretch it aft. Use a string level and make it level. This is the line the keel will follow in the last half of the hull, so make a cardboard template of the string and the bottom of the current keel profile.

Next is the new curve for the bow. This is an eyeball thing. Using a light batten spring a sweet curve from the cutwater, then aft to about aft midship (as shown above). Make the transition from the clipper knee to the new, cut back forefoot sweet. Now draw this curve on the existing deadwood (this is what gets cut off). The remaining portion of the keel gets an addition, which can be made the same way as you did originally, with 3 layers of pine.

It's unlikely you'll be able to split the layers apart without a lot of wood tear out, so set a circular saw to the thickness of the outer layer, then cut a portion of the outer layer off, with multiple passes of the saw. Knock out the pieces with a chisel and sand it smooth enough to receive new 1 by stock. This method will let you sandwich the inner layer between the new pieces of the deeper outer layer.

Naturally, this is the Cliff's Notes description, but you should get the idea. It's more a matter of balls then brains. It takes some intestinal fortitude to cut your well made keel, so man up and take the plunge. The keel profile, if similar to the above drawing will be fine. It will not be any deeper then the stock profile and it'll work better. Drop me an email and I'll send you some specs.

Paul, you make a convincing argument, and the pictures look right to my inexperienced eye.  I don't expect to need a barn door rudder, since most of my sailing will be in relatively deep water. Maybe I should plan on building something like your first illustration from the very beginning? The only worry I have is if the keel is strong enough not to snap over if I hit a rock. I guess I could ass a block of wood on the inside, over the bottom. Probably an overkill.

If the draft remains the same or is slightly increased by a few inches (50 - 75 mm), then no internal reinforcement is necessary, just a healthy fillet on the outside. If you increase draft more then 15", you should consider a taped seam (two layers of 12 ounce, 45/45 biax over a big fillet) and/or a keel batten on the inside of the boat. The keel batten would just be a 1x4 or 1x6 glued to the bottom planking and lagged to the deadwood assembly from the inside of the boat. An increased draft will exponentially improve the windward ability of these boats. The deeper it is over the stock depth, the better, so decide how much you can "afford" and add draft if you can. Where I live shoal draft is a must, but many don't have nearly the issues we Floridians have.

Given a choice of the above keel profiles, the bottom one will produce the best results, in terms of helm response, maneuverability, windward ability, etc. The full length keel is for those interested in a traditional shaped keel, with a logical (and typical) profile. The advantage of a full length keel is it tracks like a freight train and if a barn door is fitted, offers considerable protection to it. A full length keel will "lie" better when you need to take a break or tough out a storm.