Rudder Blade - Keeping it Locked Down and on the Transom.

INDEX - Pintle lock, Blade lock, Construction, Operation, Prop Damage, Moored.

NOTE - After fours years of use with my block and tackle blade pull down system the rudder blade has some unexpected wear around the pivot hole and in the pull up bolt hole. So I've developed a new solution for both and updated the text and diagrams as per below.  _________________________________________________________________________________________________________________

There are two rudder versions for the SJ23, fixed and kick up. The fixed version is for sailing in deep water where you seldom or never expect the bottom to come up to 'touch' the hull. The kick up version is for sailing in shallow water where the bottom may occasionally come to touch the rudder. The kick up version has the additional safety advantage of protecting the blade and the transom in the event of an accidental grounding. This same safety feature also allows the party animals to hit the beach by allowing the sandy bottom to push the blade up. Notice I said sand, NOT ROCKS! I don't know about anybody else, but I've never been able to lift the blade by hand as I approached the beach. I find the reach into the murky depths just a wee bit beyond my hands! 

The factory designed kick up rudder shown below left, incorporates several loops of heavy duty bungee cord at the forward side of the blade hinge. Their purpose is to hold the blade down for normal sailing, whatever that is. The bungee cords are looped between two holes at the leading edge of the rudder hinges; a 1" hole through the top of the blade and a 1/2" hole through the bottom of the rudder head. For proper performance, the bungee cord must be replaced annually. What a pain for system that doesn't work well! 

There are several drawbacks to the bungee cord system;

1. The blade pivots aft (lifts) with boat speed. The faster the boat goes, the further the blade pivots. Sometimes the blade will pivot back so far that when the tiller is relaxed, the blade pops up to the surface. What an annoying habit. Not exactly the situation you want when the wind is blowing! A trailing blade creates heavy, sloppy steering that loads up the rudder head with incredible forces. Something will eventually break. I've been in situations with Panache where this was downright dangerous with a novice bunch on board. So much for a relaxing Sunday afternoon of sailing. 
2. At hull speed the loops of bungee cord create a rooster tail that soaks the crew in the cockpit with very fine mist in a following breeze. Nice on a hot day but miserable on a cool day. They also generate a loud burbling sound that is difficult to talk over. 
3. Pushing off a beach or backing up in shallow water is difficult impossible, with the bungee cord driving the blade into the bottom. It's especially grating to hear this on gravel or rocks! You are either forced to lift the blade off the bottom by hand or to remove the rudder from the transom. In either case, I'll guarantee that the winds will push the boat back to the beach before you can reattaching the rudder. Isn't this where you just came from? You get the picture don't you? This system just doesn't work and that's putting it nicely. 

If you have a fixed rudder, you only have to consider locking the pintle.

1 - PINTLE LOCK - The factory stainless steel lock down spring is not particularly strong and is woefully inadequate for the job. Quite frankly this technique belongs on a dinghy, not on a cruising boat. The sooner you replace this lock, the sooner you will have a safer boat. Consider Frank's experience. "I was sailing in 2 to 3 foot high waves, winds at about 20 knots and gusting higher. I was moving pretty much at hull speed when the rudder came off the transom, held only by my hand on the tiller and the Tiller Tamer line! We immediately lost steerage, both sails luffing like mad in the wind, the boat bouncing crazily in the waves, leading to an unintended jibe while I tried to reinsert the pintles in the gudgeons. Under these conditions the water pressure on the rudder makes this a monumental task, but we eventually succeeded and got underway again. The force on the rudder during this episode was great enough to bend the pintle slightly to make reinstalling the rudder a challenge. The stainless steel pintle is too stiff to straighten with a vice grip on board the boat! The total loss of rudder/steerage in strong winds/waves is a very unpleasant, and possibly a dangerous situation." 

The point to note is that the rudder CAN pop up and out of the gudgeons through wave action when the boat is in a trough and the stern/rudder is lifted by a wave. The reason for this is that the foam cored rudder floats and the small metal spring that is designed to lock the rudder to the transom isn't strong enough to keep it attached. One solution is to install a short, strong bungee cord between the lower gudgeon and hook it to the hole in the upper pintle. Replace the bungee annually as it will fatigue with exposure to UV light. Another solution is to slip a hair pin or cotter pin through the hole in the upper pintle. Secure the pin to the rudder with a short line so you don't loose it. Regardless of which technique you use, it MUST not come off on its own and you should be able to operate it without tools. 

If a pintle bends, you can make a temporary one from a (4 x 3/8)" stainless steel bolt. Once the bolt is inserted in the rudder head, drill a small hole through the side to accept a cotter or roll pin to secure it. Use a marine sealant around the pin to prevent movement.  The lower pintle should be the longer than the upper one to ease installing the rudder pintles in the gudgeons--i.e... put the lower one in first and the upper one second. You'll appreciate this little bit of forethought when you have to install the rudder on the transom as Frank did. 

2 - BLADE LOCK - My first solution to locking the blade down was to replace the old bungee cord. When that didn't work I added more loops of the same gauge cord. That didn't work either. Then I replaced it all with heavy duty bungee cord. Unfortunately it was so strong that I could no longer lift the blade manually but it could still release for beaching. Despite these "fixes" the blade still managed to pivot itself backwards resulting in heavy steering and loss of speed. A friend of mine suggested to install a 1/4" wood dowel through both the rudder head and the blade, thereby locking the blade in the down position. He used this technique and claims that the wood is soft enough that it will shear off clean against the aluminum rudder head without damaging the rudder blade. Add a little moisture from the water and the wood breaks even easier! He also suggested carrying spare dowels, just in case. Eventually a person gets tired of a design that doesn't work and I considered using this technique, knowing full well that it's totally unsuitable for the shallow waters I sail on. After much wine and beer thought provoking ideas around the campfire (alcohol kills the weaker brain cells!), the proverbial light bulb lit up; use a block and tackle to pull and hold the blade down, make it internal in the rudder head so it can't be seen, and make it convenient to release for beaching. Voila.

1. I also considered the external control line solution shown at right. A nice feature of this design is that the line can also hold the rudder blade up for shallow water mooring or tight docking. It should be noted that most SJ23 rudders cannot be tipped up this high.  To create the extra pivot room the owner shortened the back spacer block in the rudder head. I now moor Panache with the blade up and she behaves much more civil at the mooring.  Besides being easier on the rudder and fittings, the blade is also protected in the event of an accidental grounding. Something always worth considering! Another point to consider about the rudder blade is wear and tear and delamination. With the blade out of the water it can't absorb water and doesn't fatigue while steering the boat at the mooring. 
2. While I think that a dowel works perfectly fine when sailing in deep water, I often motor in shallow water and have to lift the blade to clear the bottom. Lifting the blade is also a great way to shed weeds or to scoot over a shallow sand bar. So I installed an internal 4to1 block and tackle system between the leading edge of the blade and the aft side of the rudder head as shown below right. The free end of the line exists out the back of the rudder head and is guided over the top where it's tied to the tiller for ready use. The system works like a charm, both to hold the blade down and to release it quickly to allow the blade to float to the surface. 

Another reason why I developed this system was to lift the blade while motoring to prevent the propeller from damaging the blade. If you turn the rudder far enough to starboard then the blade will touch the outboard propeller. I haven't had time yet to install a permanent solution but in the mean time I can raise and lower the blade to move it away from the propeller. The blade can be damaged from a myriad of other reasons so I won't bother to describe them all. See Tech Tip B09. 

CONSTRUCTION - Referring to the diagram below right, the first step is to imbed a 3/8" stainless steel bolt into the top of the blade to hold the turning block. 

1. Using the factory bungee hole in the blade as a target, drill a 3/8" diameter hole down the center of the blade, aiming for the center of the bungee hole.
2. An anchor bolt is the perfect solution for anchoring the bolt. Make the round nut or anchor from 3/4" OD rod or thick wall tubing. Drill a hole across it, through both sides (center), and tap the holes to receive the NC thread of the 3/8" bolt. Enlarge the bungee cord hole to hold the round nut. For a detail view, click on the threaded end of the rod in the picture below.
3. Gouge out 1/4" of exposed foam from the inside surface of the blade hole. Fill the 1/4" depression with epoxy flush to the edge of the hole. This creates compression strength between the two halves of the rudder blade and prevents water absorption into the foam. Sand the epoxy smooth.
4. Insert the round nut into the blade hole aligning the threaded hole to receive the bolt. 
5. Slip a stainless bracket (to hold the small sheave for terminating the bottom end of the block and tackle) under the head of the 3/8" bolt and push the bolt into the rudder blade hole, screw it into the round nut you previously made. 
6. Seal the blade hole with Sikaflex for future disassembly. 
7. A couple of 1" double block are used for the internal block and tackle. The top block is a surface mount style and screwed to the inside of the wood spacer at the back of the rudder head. A 1" Harken double block is used for the bottom. The free end of the 1/4" control line exits through the wood spacer at the back and goes to a jam cleat mounted outside the rudder. Drill a 5/16" angled hole for the control line and sand the hole smooth to minimize line wear. Leave the line long enough to conveniently dangle over the transom into the cockpit. 

You now have a 3 to 1 purchase that is strong enough to pull the blade down while sailing. (To be a true 4 to 1 purchase, the dead ended line should be attached to the bottom block).

HINT: If you coat the upper end of the blade with epoxy saturated with carbon graphite powder it will create an extremely hard and slippery surface, making it easier to pivot the blade. Mix the carbon graphite about 10% by volume. It makes a very black soupy mess! To complete the job, sand off any high spots and insert a bushing or stainless tube in the pivot hole of the blade. Make the tube is ever so slightly longer than the thickness of the blade. This way you can tighten the pivot bolt and rudder head against the tube to eliminate sideways play without jamming the blade.

Factory design with bungee cords to hold the blade down.

My design using a block and tackle to PULL the blade down.
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OPERATION - The rudder is streamlined with the internal block and tackle and the system has sufficient mechanical advantage to pull the blade down, regardless of the hull speed or wind direction. So if you decide to scoot through some shallow water to win the race, there is enough mechanical advantage to pull the blade down when you return to deep water, all without stopping the boat. A word of caution about sailing with the blade up. The forces on the rudder head and tiller can be tremendous when sailing upwind, especially when you add a few waves that you have to steer for. 

CAUTION: With the block and tackle locking system described in this Tech Tip, you MUST be ready to release the locking line when approaching shallow water. This is why it's so important to have an accessible and quick to release system.  Failure to release the blade could result in structural damage to the rudder blade and/or the transom if you hit the bottom too hard. But then this would be no different than grounding with a fixed rudder. An improvement on locking the control line with a jam cleat is the Clamcleat® CL257 mini auto-releasing rope cleat. The advantage of the CL257 is that it has an adjustable release load setting that gives peace of mind for the single handed sailor who is too busy looking after something else. It never fails that fifty things happen at the same time! 

Here is another hold down and lift system Simpler to install and repair but you will get spray and noise from the lines in the water. 

PS: For those of you who don't have a depth sounder, a fully lowered center board touches the bottom before the rudder!   Hmmm.

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