Steel hull wooden everything else?

here is the Lyoyds approved) rudder, ss 2203 stock which has tensile of 89000 if I remember rightly, and macrocarpa timber build up laminate on ss tangs We built a very strong stock support inside,and the bottom of the rudder was sacrificial, there are lots of whales down here
you can see how the rudder fit the hull

 

We're not entirely sure about what we are looking at but my wife and I are really excited. I'm thinking do the whole thing in steel, bulkheads included (unless you have another suggestion) except inside furniture, lead for the keel and what do you honestly think about the keel should I change to a fin and spade or just keep what I've got. I've got a plasma cutter and every type of grinding cutting tool you can think of. Ive also got a crane to lift the entire hull if I need more room to accomodate a deeper keel. The cradle that she is currently in needs to be re stuanchioned anyway for the hull to be faired above the waterline. There is still a 300mm x 300 mm hole where the rudder needs to go. The time I'm going to save by doing the deck/cabin in steel and all the fitings etc will certainly offset any time spent building a deeper keel to accomodate the extra weight added by using steel up top

 

the boat is not big on waterplane, she is weight sensitive, please wait til the dwgs get to me, and you have a strong hull, you do not really need w/t b/h
be patient, if you can send pics of skeg area

 

Steel hull

Stick with what you've got. For a cruising yacht, what you've got for underwater shape is perfect and any change would be a screwup. Building a sacrificial rudder is as foolish as a car who's wheels are designed to fall off if she takes a corner too fast. Duhh!!!
I've sailed amoung whales for decades and never found one dense enough to hit my rudder. If I did, I'd put a few sharp blades on it, and they'd learn quickly
Go steel for the shell and plywood for bulkheads, where steel would be no advantage.
Lazyjack. You say Lloyds doesn't deal with boats under 80 ft? That makes all the Lloyds debates on origami boats I build, totally redundant. Not many cruisers out there in boats over 80 ft. That makes Lloyds redundant for 99% of offshore cruisers.
Thanks
Brent

 

i am tired to death of
of your stuck in the groove mentality, go do some work
I also posted what was on Caper
i make all my rudders from ss , 2203 stock, and one eigth skins plug welded to frames

 

Building a rudder out of 1/8th inch plate plug welded to the stock is a fraction the time and money of any wooden rudder between tangs and a much stronger ,lighter and more reliable rudder.It's the only logical way to go.
Of course , outboard rudders make the stock the top of the rudder , eliminating stock questions and drasticaly simplifying self steering and inside steering.
A client watched a guy build a plywood and glass rudder for a westsail 32. He took weeks to build it , then had to hire a crane to ship it. A steel rudder would have taken a couple of hours to build and could be shipped by one guy by hand.
Lazy jack , expect your childish rants to be ignored with the contempt they deserve. We are all getting rather sick of such childishness .
Brent

 

this is the first Cape I built, the owner wanted steel, but we offered abetter deal in alloy
She circumnavigated , over 4 year period
TREE, YOU NEED SET UP THE BOAT level , and then dumpy the difference in Height from the stem to the stern at center, I can then loft in a fair deck cl, you may get the boat level, if you find some water lines on the frames or the floors(those steel bits across the bottoms of the frames) look at same height

 

Nice boat Lazy but steel for me no way. My welds look like a bird has tacken a crap on the plate

 

Here are some photo's of the skeg as is. You mentioned the rails in the floor being level with each other. That is true. The,( I guess), intended floor beams are all aligned and level with each other..........A simple matter of placing a spirit level north south and east west along the floor beams to level the floor and hull as a whole? Fortunately I've got the entire hull and cradle sitting on a concrete slab. I was thinking of leveling the cradle itself but I guess your way levels the floor of the boat when it is in the water assuming other weight factors are in place.

Ps the last photo is Auckland city at night coming in to Waitemata harbour. taken with my cell phone in the rain.

 

TREE, YOU NEED SET UP THE BOAT level , and then dumpy the difference in Height from the stem to the stern at center, I can then loft in a fair deck cl, you may get the boat level, if you find some water lines on the frames or the floors(those steel bits across the bottoms of the frames) look at same height[/QUOTE]

So, I would level the floor and then run two string lines with levels on each one from the very front of the boat and one from the stern and then measure the distance between the two strings at the centre of the boat. Given that the floor is level and the two string lines are also level it should not matter where along the length of the hull I measure them given that I am interpreting you correctly. Although It would be bet to place the string levels over the centre of the hull to account for the slight sag in the string and measure from there.
Am I on the right path?

 

Steel hull

You definitly have to beef up that skeg. Read the discussion on skeg failures on metalboatsociety.com.
Several large transverse webs going into that skeg and spreading the load widely across the hull would be a good idea. The skeg can also be made into a keel cooler, by running a cooling water pickup pipe into the bottom, and the outlet with an elbow on it , into the top of the skeg, at the front.
Aluminium is a a great material for cabins and wheelhouses and possibly cockpits, but not so good for hulls. Its extremely difficult to find an effective antifouling that won't eat it.
All your welding needs are long hours burning rod on bits of scrap.
Brent

 

Sorry Brent what do you mean "al your welding needs are long hours burning rods on bits or scrap?

 

Stick welding is 95% practice and 5% theory . If you take a welding course it will be long hours of practice, which you can do yourself , with a few books from the local library to inform you of what you are trying to achieve.
Get a book, get a pile of scrap and a box of rods, then teach yourself. It aint that complicated or difficult, mostly hand- eye co-ordination.
Brent

 

Thanks for the advice I've actually been welding for quite some years. That is about the one thing in this project that I know I can do.

 

Tree,
I suggest; get Colvin's book & build the deck in steel. The hull/deck joint has to be very strong & solid. Make sure water, fluids & debris can travel to common area(s) for clean-out. Lazeyjack could probably draw up deck construction & bulkhead plans for you. Best of luck. Better use some of your wife's ideas, or you might find yourself on the couch!
Mike