Rudder Seam Crack from lightning, or no?

[Max Sail]

I'm considering an Ingrid which was struck by lightning in 2011. The hull appears ok to my newbie eyes, but the rudder has a seam crack on the leading and tailing edges. Is this a standard problem you might expect to see on an old boat, or more likely a result of the lightning exiting out the prop shaft?

Would love to fix up this boat, but could I ever be sure the hull is sound and not compromised by lightning in some way I'd never discover until rounding Cape Horn in a gale when the hull opens up a gaping hole?

Pics here...
http://www.yachtworld.com/core/listi...url=&imc=pg-fs

PS: Is that picture labeled 'ground plate' really just a standard electrolysis zinc? Or actually a lightning ground plate?

[roverhi]

A thorough inspection out of the water should turn up any issues with lightning caused damage. Lots of boats have been hit by lightning and are still doing just fine. Of course the electronics should all be toast and need replacing. If it had been a serious strike, the box section masts should have exploded. The fact that so few of the electronics were damaged

That is a nice big crack on the rudder. Shouldn't be an issue though. Just laminate a few layers of glass with epoxy on the leading and trailing edge,, and Bob's your uncle. No armature or other metal in the internals that could be cause for concern with that outboard rudder. Just read the write up on the boat. A wood core in the rudder is a bit of a concern. The rudder is essentially a monocoque structure getting it's strength from the skin. Would want to explore why the rudder cracked open so badly. The Westsail for one, used a foam core in the rudder and haven't had many issues that weren't fixed by a little glass.

Another little misconception is that putting ballast low and spread out is good. It does lower the center of gravity but adds weight to the ends which contributes to hobby horsing. From experience with our Westsail, getting weight out of the ends helps when beating into a chop. i wouldn't be concerned about the boiler punching ballast other than it's lower weight density than lead. Our old boat has composite punchings and lead ballast. It's spent it's entire life in the tropics with no ill effects.

Ditch the staysail boom, get a decent anchor and all chain rode and you could be off to see the world. For the price, that's a lot of boat.

[ozskipper]

I agree with the above except the weight comment. The further apart the weights the more stable the vessel- sort of. It would tend to Punch into waves instead of riding up and over them for example.

There will be smarter person than me here who will no doubt chime in and explain that better.

[GordMay]

I wouldn't expect an outboard rudder to be a likely lightning exit point.

You might check out the Ingrid Owners site.

➥ Welcome Aboard - Ingrid Site

➥ Ingrid owners

From their brochure:
“RUDDER:
Heavy glass laminate wrapped around Klegecell foam core. Installed with massive bronze gudgeons and pintles. It wasn't until we felt we could build a rudder strong enough to hold 13 tons of boat adrift backwards that we finally felt secure in offering a rudder for the Ingrid.”
➥ Ingrid Brochure

[boatpoker]

Given the location of the boat it is likely that the rudder core was wet and the 8% expansion of water freezing caused the fractures.

[zeehag]

f you like the boat and price then fix the rudder. if not, pass on it.

welcome and good luck with this.

[roverhi]

Not only no but hell no!!!! Look at the typical racing boat. They are designed for one thing, speed under sail. Every flat out racing boat i've seen has all weight centered with a big empty cavern forward and aft.

Weight in the ends of a boat cause it to hobby horse as well as slow the boat punching into a wave. The old body in motion tends to stay in motion thing. When you have mass in the ends, the bow will lift in a wave and continue up as the mass tries to stay in upward motion and the opposite as gravity takes over and the bow goes down. Couple that with reduced buoyancy in the stern of the Atkins design and the boat tends to waste motion going up and down and not forward. BDTD.

It's also easier to propel a boat over a wave than through it unless specifically designed to do so. Had this glaringly demonstrated when I sailed our Westsail without the 230' of 3/8" chain in the bow. Launched the boat and sailed it to SoPac and back with the chain in place. When we got back pulled the chain out and went sailing. Was amazed at the difference as the bow would rise to a wave with little diminution of speed. With the chain in place it tended to punch into the waves and slowing down before the bow would rise. Not so noticeable beating into long ocean swells but very much so beating into short, choppy seas often seen close to shore.

That's the reason that the W32 has a reputation for being a poor sailing boat to weather especially in light air. We had no problem in the long open ocean swells once doing 5 days hard on the wind reeling off a steady 5k day in day out. Light air and a chop and the boat would actually sail sideways if we tried to oinch up. The Ingrid won't be as effected as the W32 because the bow is much finer and more efficient going to weather. Still, the Ingrid design would sail much better with more centered all lead ballast. Lead in the middle is the reason that the Alajuela 38 sails better and faster than the more traditional Ingrid builds. Of course, the typical Alajuela sells for 3 times what they are asking for this Ingrid.

Originally Posted by ozskipper

I agree with the above except the weight comment. The further apart the weights the more stable the vessel- sort of. It would tend to Punch into waves instead of riding up and over them for example.

There will be smarter person than me here who will no doubt chime in and explain that better.

[Max Sail]

Appreciate the input all. So much yet to learn...

[ozskipper]

Originally Posted by roverhi

Not only no but hell no!!!! Look at the typical racing boat. They are designed for one thing, speed under sail. Every flat out racing boat i've seen has all weight centered with a big empty cavern forward and aft.

Weight in the ends of a boat cause it to hobby horse as well as slow the boat punching into a wave. The old body in motion tends to stay in motion thing. When you have mass in the ends, the bow will lift in a wave and continue up as the mass tries to stay in upward motion and the opposite as gravity takes over and the bow goes down. Couple that with reduced buoyancy in the stern of the Atkins design and the boat tends to waste motion going up and down and not forward. BDTD.

It's also easier to propel a boat over a wave than through it unless specifically designed to do so. Had this glaringly demonstrated when I sailed our Westsail without the 230' of 3/8" chain in the bow. Launched the boat and sailed it to SoPac and back with the chain in place. When we got back pulled the chain out and went sailing. Was amazed at the difference as the bow would rise to a wave with little diminution of speed. With the chain in place it tended to punch into the waves and slowing down before the bow would rise. Not so noticeable beating into long ocean swells but very much so beating into short, choppy seas often seen close to shore.

That's the reason that the W32 has a reputation for being a poor sailing boat to weather especially in light air. We had no problem in the long open ocean swells once doing 5 days hard on the wind reeling off a steady 5k day in day out. Light air and a chop and the boat would actually sail sideways if we tried to oinch up. The Ingrid won't be as effected as the W32 because the bow is much finer and more efficient going to weather. Still, the Ingrid design would sail much better with more centered all lead ballast. Lead in the middle is the reason that the Alajuela 38 sails better and faster than the more traditional Ingrid builds. Of course, the typical Alajuela sells for 3 times what they are asking for this Ingrid.

The idea of centering weight is to allow the boats bow and stern rise and fall without being slowed by a punching bow.

To give you an example of where you went wrong in your explaination.

think of a small boat at anchor with boom out to port and Pole out to starboard. Add two 20 litre buckets of water to the far ends of each spar. Any rolling moment will be dampened. I have used the above technique on several occasions to dampen rolling moment. The same applies for for and aft weights.

Large ships will fill outboard tanks to do the same thing. Often Called U-tube tanks due to the shape. Similar versions are called Active Anti-roll tanks. http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA229278

Or think of the same principal as a general weights. If all the weight was in your hand as say a ShotPut ball. Its easy to rotate. But the same weights extened on say a Dumbell are much harder to rotate.

Btw, at no point did i say it was a good thing. I just mentioned the outcome!