posted August 13, 2005 12:53 AM               

Anyone had this problem? CL sells the new part for $310.

posted August 13, 2005 09:19 AM            

At the bottom of the rudderhead the outside layers of plywood were damaged (rotting?). So I just milled the damaged layers off for about the lower 3" using a table saw with dado blade. Then refinished the whole rudderhead with Cetol Marine.

posted August 13, 2005 09:37 AM               

If I'm not happy with the results I'll step up and buy the new part.

posted August 13, 2005 06:45 PM               

I was reading in my latest edition of Pacific Yachting about different woods (plywoods) that can be used for marine use and one they said you can use is a Baltic Birch plywood. This is a very well made plywood with about 6 to 8 layers glued together to make 3/4" and the glue used will not break down if it gets wet. How ever they say that you should still cover it, especially the ends with epoxy. I used this wood to make the new table I put inside.

I figure I could make the new rudder head for about $40.00 plus epoxy.

posted August 14, 2005 09:30 AM               

The winter after that I built another rudder and rudderhead, and tiller. Now I have two.

posted August 14, 2005 11:16 PM               

Show us a pic of it, please.

posted August 15, 2005 05:25 AM            

As Arthur stated, the lower part of the rudder head dragged through the water. So with the rudder mounted on the transom and using a straight edge against the bottom of the hull, I marked a line across the rudder head tangent to the hull. This part of the rudder head really offered no support to the rudder blade. It lacked structure.

posted August 17, 2005 02:00 PM               

The original rudder design had (to my thinking) extremely poor design without consideration of what elements of the construction were carrying what loads.

But your subsequent concern, I think, was that reducing the cheek length would increase the stress on the rudder, and increase the flex. I don't think this is a big problem. Really, forces on the rudder are not that large. The forces produced by use were successful in fracturing the gudgeon only because they had a large mechanical advantage, and they were allowed to work repeatedly over a long time.

The rudder is a strong piece of wood that can easily tolerate a few dozen pounds of side loading, probably much much more. If you were to clamp the rudder head in a vice with the rudder horizontal, and then stand on the rudder, I think the rudder head would break, not the rudder. Even with through bolting, the joint between rudder and rudder head is the weakest point.

In any case, I have not seen any deterioration of the action of the rudder as a result of reducing the cheek length.

Arthur

posted August 17, 2005 09:03 PM            

I also had cracking of the gundgen and then after welding one side I had the opposite side fail. I had converted to the thru bolting fastening at the time. Then I ended up replacing both sets of gudgeon/pintels.

Fred (civil/mechanical engineer)

posted August 18, 2005 10:33 PM               

Further to Ken's bolting, we've done a bit more fine-tuning on Shortwave's rudder. I coated the bottom 4 inches of the rudder head with West epoxy. I then painted over the epoxy with VC-17 as our rudder stays in the water all season.

The top gudgeon on the transom was a different make than the other gudgeons and pintles. The hole was just a smidge too big. This caused the rudder to wobble and it was driving me nuts. As is usual for an old boat, they didn't make the proper replacement any more but I was able to get the right size hole in a Ronstan. Used 4 bolts instead of 3, which I backed with large washers. After re-drilling the stern. Tiller also wiggled in the rudder so I built up the sides for a solid tight fit. When I epoxied the rudder it caused it to be slightly thicker so it also fits tightly between the rudder head sides. It's bolted tightly to the point that if I want to raise the rudder when going through shallows, I have to lean over and lift it by hand. All the flexing in the original setup not only robbed us of boat speed but the twisting would eventually lead to early failure of one of the components. The forces through twisting “divide and conquer”. Now if I'm twitching while holding the tiller, the whole boat twitches.

I'm with Fred on the not trimming away of material. Light is nice but strength is most important here. The Sandpipers' rudder is a bit weak to begin with so I'd be very careful to make it lighter by removing material. I think it's the result of the kick up shallow draft feature.

You can inadvertently apply a lot of force to the rudder if not careful. The light keel/centreboard makes the boat a bit sensitive. It can heal very quickly and if you try to lay off while healed by steering only, you're putting a lot of pressure on the rudder. I've seen big boats snap rudders with this action and I think you could easily do it in a Sandpiper. Make sure you let the sails out slightly before moving the rudder. The boat will level off and be easier to steer. Let the hull and sails steer the boat, not the rudder; causes less stress on equipment. Also makes the boat move faster because there is no turbulence from rudder action.

To ease pressure on the rudder and go faster downwind or gibing we shift our weight to steer the boat. When we go into a gibe we heal the boat to weather, which causes the hull to turn to leeward. Again, no pressure on the rudder and the boat moves faster. You can't do this on a large keelboat but it works beautifully on a Sandpiper. You are at one with your boat.

Shortwaves' rudder head is above the water when at anchor but slightly submerged when I'm on the stern. I'm not sure, but I think it's above water when sailed correctly. We always keep our weight well forward when sailing as you can see in this photo Stan took at the Rendezvous.

When the wind gusts, the helmsperson moves back and the tactician (crew) moves up. We sit as close as possible together and forward (Excellent quality time with your sweetie). We've got the heaviest motor and biggest gas tank in the fleet but I think we keep the stern wave breaking freely. I hope to get a slightly longer tiller extension next year so I don't have to reach so far back when forward.

posted August 18, 2005 11:03 PM               

Ken had Shortwave's mast raked quite far back because he felt it gave the boat needed weather helm. When we got our new jib, we found the helm shifted slightly so we have tilted the mast slightly forward. It was most noticeable on close reaches where there seemed to be a lot of pressure holding the rudder straight.

A balanced rig will go a long way in reducing extra pressure on your rudder. Too much weather helm = poor BS (Boat Speed). The trick is to have “just a bit” of weather helm. Ken had it with his old sails and I think we have achieved it with our new ones.

In the 70s I sailed on a boat that actually collided with a whale, ripping 80% of the rudder off. (Whales are not familiar with the right-of-way rules.) With a balanced rig and skillful sail handling the crew was able to finish the race without a rudder.

posted August 19, 2005 04:57 PM            

quote:

---

Originally posted by Darcy:
As is usual for an old boat, they didn't make the proper replacement any more but I was able to get the right size hole in a Ronstan.

---

CL Sailboats sold me an exact replacement set of gudgeons/pintels last summer.

Fred

posted August 19, 2005 10:42 PM               

The Shark fleet (that I often race with) went through similar developments. Like the Sandpiper, Sharks are an older design that didn't have high tech rudders or keel. A number of boats tried rudders like Arthur's' but discovered the best combination was a bit of a hybrid. Because the keel is still not efficient they found a longer profile worked a bit better. The larger rudder acted like a secondary keel and helped the boat point better. It's as if the original design was almost too efficient and not compatible with the slower keel. They also tended to move the rudder back for downwind control.

In the 60's, one of the Canada's Cup boats experimented with a more forward positioned rudder. (They used to let me work on it, which was really neat when you're a keen teenage sailor.) It was spectacular going upwind; nothing could touch it. In heavy winds while running though, it was very hard to control. If you've ever broached while trying to gibe in an older boat with the rudder right behind the keel (Dragon, 8 metre, etc.) you'll know what I mean.

When we sailed 14's in the 80's, guys were extending their pintles a foot or so beyond the transom to get the rudder back. I believe the rules were eventually changed to prevent this.

I'm a big fan of keeping the rudder back, especially on shorter boats. If we weren't a one-design class I'd taper the transom to the rudder, which would extend the waterline length making the boat faster. The main reason though is for stability downwind. Lynn took a few pictures of Duchess II while racing at the Rendezvous. You can see how she seems to role to windward while going downwind.
Slight rolling just after the gibe mark.

More pronounced role going downwind.

If we were racing in real windy weather, this rolling might easily become extreme. It's what Laser and Finn sailors refer to as a death role.

If you can control it, it's a very fast way to sail. When you start to role, pull in the main. You're now actually sailing by the lee, but it's very stable. When the boat heels back, let the main back out.

posted August 20, 2005 08:40 AM            

You have mentioned before the notion of moving the rudder aft of the transom for better tracking. Here is a drawing and a photo of a project that did not make it to the rendezvous. It is a rudder GANTRY that doubles as a boarding ladder. It was spawned by an earlier D'Arcy comment on rudder efficiency. Check out the links.

http://tinypic.com/av1ms4.jpg
http://tinypic.com/av1ndg.jpg

posted August 20, 2005 11:42 AM               

Will a death roll cause a crash gybe, or worse a broach? I need a little help here

Arthur's rudder is a thing of beauty!

Thanks, Eric

posted August 22, 2005 08:03 PM               

We broached on Sunday in 30 knots of wind on my Brother's 36 footer. We were surfing waves home from Grimsby when we just didn't quite lay off enough to keep the speed going down the wave. My Brother's boat is very sea kindly so it did a nice graceful broach. I think a Sandpiper would do the same. It would round up fairly quickly, spilling wind, then right it's self. A broach gets dangerous when the boom drags in the water because you can't let the sail out. A Sandpiper's boom is quite high so I don't think it would be an issue.

This boat is on a starboard tack (boom on port side) heeling to weather. In a death role, the boat rounds the other way to a broach (because it's heeled to weather ).

In a death role you heel to weather (your boom would be right up in the air) like this. This boat is on a port tack

As far as downwind stability during the race goes: In watching all the boats running we think Duchess II was rolling from the wind. Not severely enough though, to broach or role. Just showing signs of the potential if it got windy. (You guys were really pushing it for speed.) I think a Sandpiper will be very stable even in really windy weather. In extreme wind, good helming and sail control would most likely compensate for any design issues in the rudder. We've had some amazing sails in Shortwave. Running down waves with reefed main in 25 to 30 knots of wind; she's one happy boat.

When we were going upwind during the Rendezvous races, Lynn was initially on the rail (taking pictures). The traveler was out all the way, vang tight, and I had the main out enough that it was 2/3 back filled. For speed in playing the shifts we didn't keep Lynn on the rail because it slowed us down in quickly playing the shifts. We could have used a guy like Ab though. Duchess II was churning upwind almost flat; solid bow wave from driving through the waves.

posted August 23, 2005 06:58 PM               

As I understand it, when sailing wing on wing, if the wind becomes too strong, any minor shift in the boat will cause one of the sails to dump wind, while the sail on the opposite side continues to pull. This causes the boat to heel towards the stronger sail. The heeling causes to stronger sail to dump air and it becomes the weaker sail. Meanwhile the previously weaker sail has stood up and is now the stronger sail, pulling like a mule, so it pulls the boat back. This continues, and the oscillations build with every roll. This quickly tosses the boat over on its side unless you IMMEDIATELY adjust one of the sails so that the back and forth forces are halted, you must disrupt the pattern.

Although I only experienced it once, I will never mistake the feeling of that roll, starting so small and becoming ferrosious and uncontrollable. Next time I feel that, I'm pulling in on a sheet.

posted August 25, 2005 01:12 PM               

I think the real secret to our speed is the team and how we work together. I focus only on the jib and driving the boat through the waves. The crew (or tactician as we would say) keeps track of the other boats, course and feeds me the information. That way I'm always focussed on the boat. If I took my eyes off the sails, we would slow down quite a bit. In other words, the smart one is sailing the boat (Lynn). She spots shifts faster than I would because she can look at the compass and see the gusts comming.

From our International 14 days, sail handling is a cooperative effort as well. 2 of us to pull the jib in when it's windy which speeds our tacking. In other boats Lynn has also worked the traveller which we can't do on Shortwave.

We now have a new mainsail as well. Although the same size as our old sail, it has some roach. Its' shape is easier to control too. We can make it fuller for light air or flatten the shape in the windy stuff. Over the winter I'll be adding outhaul and cunningham controls that lead to the cabin top. Then we can fool around with sail shape a little easier.

So look out next year guys; Shortwave will be one hot boat.